{"group":{"id":1,"name":"Community","lockable":false,"created_at":"2012-01-18T18:02:15.000Z","updated_at":"2025-12-14T01:33:56.000Z","description":"Problems submitted by members of the MATLAB Central community.","is_default":true,"created_by":161519,"badge_id":null,"featured":false,"trending":false,"solution_count_in_trending_period":0,"trending_last_calculated":"2025-12-14T00:00:00.000Z","image_id":null,"published":true,"community_created":false,"status_id":2,"is_default_group_for_player":false,"deleted_by":null,"deleted_at":null,"restored_by":null,"restored_at":null,"description_opc":null,"description_html":null,"published_at":null},"problems":[{"id":2431,"title":"Power Times (of the day)","description":"Many times throughout the day can represent mathematical equations. In this problem, we focus on times that represent powers. For example, 8:23 can be written as 8=2^3. Write a function that determines if the given time (restricted to three digits in 12-hour time, 1:00 to 9:59) is a power time. There are four types that are categorized here, and a given time can fit more than one category:\r\n\r\n - equation written forward, \"=\" doesn't coincide with \":\" --\u003e add 1 to output (e.g., 2:38)\r\n\r\n - equation written forward, \"=\" does coincide with \":\" -- \u003e add 100 to output (e.g., 8:23)\r\n\r\n - equation written backward, \"=\" doesn't coincide with \":\" --\u003e add 10 to output (e.g., 3:28)\r\n\r\n - equation written backward, \"=\" does coincide with \":\" --\u003e add 1000 to output (e.g., 9:23)\r\n\r\nExamples of combination times include 4:22 (1100 since 4=2^2 and 2^2=4) and 1:31 (1001 since 1^3=1 and 1^3=1).\r\n\r\nThis problem is related to \u003chttp://www.mathworks.com/matlabcentral/cody/problems/2432-equation-times-of-the-day  Problem 2432\u003e and \u003chttp://www.mathworks.com/matlabcentral/cody/problems/2433-consecutive-equation-times-of-the-day Problem 2433\u003e.","description_html":"\u003cp\u003eMany times throughout the day can represent mathematical equations. In this problem, we focus on times that represent powers. For example, 8:23 can be written as 8=2^3. Write a function that determines if the given time (restricted to three digits in 12-hour time, 1:00 to 9:59) is a power time. There are four types that are categorized here, and a given time can fit more than one category:\u003c/p\u003e\u003cpre\u003e - equation written forward, \"=\" doesn't coincide with \":\" --\u0026gt; add 1 to output (e.g., 2:38)\u003c/pre\u003e\u003cpre\u003e - equation written forward, \"=\" does coincide with \":\" -- \u0026gt; add 100 to output (e.g., 8:23)\u003c/pre\u003e\u003cpre\u003e - equation written backward, \"=\" doesn't coincide with \":\" --\u0026gt; add 10 to output (e.g., 3:28)\u003c/pre\u003e\u003cpre\u003e - equation written backward, \"=\" does coincide with \":\" --\u0026gt; add 1000 to output (e.g., 9:23)\u003c/pre\u003e\u003cp\u003eExamples of combination times include 4:22 (1100 since 4=2^2 and 2^2=4) and 1:31 (1001 since 1^3=1 and 1^3=1).\u003c/p\u003e\u003cp\u003eThis problem is related to \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/2432-equation-times-of-the-day\"\u003eProblem 2432\u003c/a\u003e and \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/2433-consecutive-equation-times-of-the-day\"\u003eProblem 2433\u003c/a\u003e.\u003c/p\u003e","function_template":"function out = power_time(time)\r\n out = 0;\r\nend","test_suite":"%%\r\ntime = '2:38';\r\ny_correct = 1;\r\nassert(isequal(power_time(time),y_correct))\r\n\r\n%%\r\ntime = '8:23';\r\ny_correct = 100;\r\nassert(isequal(power_time(time),y_correct))\r\n\r\n%%\r\ntime = '3:28';\r\ny_correct = 10;\r\nassert(isequal(power_time(time),y_correct))\r\n\r\n%%\r\ntime = '9:23';\r\ny_correct = 1000;\r\nassert(isequal(power_time(time),y_correct))\r\n\r\n%%\r\ntime = '7:22';\r\ny_correct = 0;\r\nassert(isequal(power_time(time),y_correct))\r\n\r\n%%\r\ntime = '1:31';\r\ny_correct = 1001;\r\nassert(isequal(power_time(time),y_correct))\r\n\r\n%%\r\ntime = '4:22';\r\ny_correct = 1100;\r\nassert(isequal(power_time(time),y_correct))\r\n\r\n%%\r\ntime = '1:02';\r\ny_correct = 1000;\r\nassert(isequal(power_time(time),y_correct))\r\n\r\n%%\r\ntime = '4:12';\r\ny_correct = 0;\r\nassert(isequal(power_time(time),y_correct))\r\n\r\n%%\r\ntime = '5:15';\r\ny_correct = 1001;\r\nassert(isequal(power_time(time),y_correct))","published":true,"deleted":false,"likes_count":2,"comments_count":8,"created_by":26769,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":96,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":45,"created_at":"2014-07-15T18:00:06.000Z","updated_at":"2026-01-15T14:21:57.000Z","published_at":"2014-07-15T18:00:06.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eMany times throughout the day can represent mathematical equations. In this problem, we focus on times that represent powers. For example, 8:23 can be written as 8=2^3. Write a function that determines if the given time (restricted to three digits in 12-hour time, 1:00 to 9:59) is a power time. There are four types that are categorized here, and a given time can fit more than one category:\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"code\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003e\u003c![CDATA[ - equation written forward, \\\"=\\\" doesn't coincide with \\\":\\\" --\u003e add 1 to output (e.g., 2:38)\\n\\n - equation written forward, \\\"=\\\" does coincide with \\\":\\\" -- \u003e add 100 to output (e.g., 8:23)\\n\\n - equation written backward, \\\"=\\\" doesn't coincide with \\\":\\\" --\u003e add 10 to output (e.g., 3:28)\\n\\n - equation written backward, \\\"=\\\" does coincide with \\\":\\\" --\u003e add 1000 to output (e.g., 9:23)]]\u003e\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eExamples of combination times include 4:22 (1100 since 4=2^2 and 2^2=4) and 1:31 (1001 since 1^3=1 and 1^3=1).\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eThis problem is related to\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:hyperlink w:docLocation=\\\"http://www.mathworks.com/matlabcentral/cody/problems/2432-equation-times-of-the-day\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProblem 2432\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e and\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:hyperlink w:docLocation=\\\"http://www.mathworks.com/matlabcentral/cody/problems/2433-consecutive-equation-times-of-the-day\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProblem 2433\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\"},{\"partUri\":\"/matlab/output.xml\",\"contentType\":\"text/xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\" standalone=\\\"no\\\" ?\u003e\u003cembeddedOutputs\u003e\u003cmetaData\u003e\u003cevaluationState\u003emanual\u003c/evaluationState\u003e\u003clayoutState\u003ecode\u003c/layoutState\u003e\u003coutputStatus\u003eready\u003c/outputStatus\u003e\u003c/metaData\u003e\u003coutputArray type=\\\"array\\\"/\u003e\u003cregionArray type=\\\"array\\\"/\u003e\u003c/embeddedOutputs\u003e\"}]}"},{"id":2432,"title":"Equation Times (of the day)","description":"Many times throughout the day can represent mathematical equations. In this problem, we focus on times that include the four basic operations (+,-,*,/). For example, 6:17 can be written as 6=1+7. Write a function that determines if the given time (restricted to three digits in 12-hour time, 1:00 to 9:59) is an equation time, and if so, which basic operation it uses. There are also four types of equations that are categorized here, and a given time can fit more than one category:\r\n\r\n - equation written forward, \"=\" doesn't coincide with \":\" --\u003e add 1 to output (e.g., 2:35, 2+3=5)\r\n\r\n - equation written forward, \"=\" does coincide with \":\" -- \u003e add 100 to output (e.g., 2:53, 2=5-3)\r\n\r\n - equation written backward, \"=\" doesn't coincide with \":\" --\u003e add 10 to output (e.g., 3:26, 6=2*3)\r\n\r\n - equation written backward, \"=\" does coincide with \":\" --\u003e add 1000 to output (e.g., 4:28, 8/2=4)\r\n\r\nNote that some of these combinations are tied to each other due to the commutative nature of + and * and the inverse relation of +,- and **,/. The output should be a 4x2 matrix with 0s or 1s in the first column dependent on whether each operation (+,-,*,/) is applicable to a given time and the totals in the second column. Examples include: \r\n\r\n4:22 | out = [1 1100; 1 1; 1 1100; 1 1]; since 4=2+2, 2+2=4; 4-2=2; 4=2*2, 2*2=4; 4/2=2.\r\n\r\n5:15 | out = [0 0; 0 0; 1 1111; 1 1001]; since 5*1=5, 5=1*5, 5*1=5, 5=1*5; 5/1=5, 5/1=5.\r\n\r\nThis problem is related to \u003chttp://www.mathworks.com/matlabcentral/cody/problems/2431-power-times-of-the-day Problem 2431\u003e and \u003chttp://www.mathworks.com/matlabcentral/cody/problems/2433-consecutive-equation-times-of-the-day Problem 2433\u003e.","description_html":"\u003cp\u003eMany times throughout the day can represent mathematical equations. In this problem, we focus on times that include the four basic operations (+,-,*,/). For example, 6:17 can be written as 6=1+7. Write a function that determines if the given time (restricted to three digits in 12-hour time, 1:00 to 9:59) is an equation time, and if so, which basic operation it uses. There are also four types of equations that are categorized here, and a given time can fit more than one category:\u003c/p\u003e\u003cpre\u003e - equation written forward, \"=\" doesn't coincide with \":\" --\u0026gt; add 1 to output (e.g., 2:35, 2+3=5)\u003c/pre\u003e\u003cpre\u003e - equation written forward, \"=\" does coincide with \":\" -- \u0026gt; add 100 to output (e.g., 2:53, 2=5-3)\u003c/pre\u003e\u003cpre\u003e - equation written backward, \"=\" doesn't coincide with \":\" --\u0026gt; add 10 to output (e.g., 3:26, 6=2*3)\u003c/pre\u003e\u003cpre\u003e - equation written backward, \"=\" does coincide with \":\" --\u0026gt; add 1000 to output (e.g., 4:28, 8/2=4)\u003c/pre\u003e\u003cp\u003eNote that some of these combinations are tied to each other due to the commutative nature of + and * and the inverse relation of +,- and ,/. The output should be a 4x2 matrix with 0s or 1s in the first column dependent on whether each operation (+,-,*,/) is applicable to a given time and the totals in the second column. Examples include:\u003c/p\u003e\u003cp\u003e4:22 | out = [1 1100; 1 1; 1 1100; 1 1]; since 4=2+2, 2+2=4; 4-2=2; 4=2*2, 2*2=4; 4/2=2.\u003c/p\u003e\u003cp\u003e5:15 | out = [0 0; 0 0; 1 1111; 1 1001]; since 5*1=5, 5=1*5, 5*1=5, 5=1*5; 5/1=5, 5/1=5.\u003c/p\u003e\u003cp\u003eThis problem is related to \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/2431-power-times-of-the-day\"\u003eProblem 2431\u003c/a\u003e and \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/2433-consecutive-equation-times-of-the-day\"\u003eProblem 2433\u003c/a\u003e.\u003c/p\u003e","function_template":"function out = equation_time(time)\r\n out = 0;\r\nend","test_suite":"%%\r\ntime = '4:22';\r\ny_correct = [1 1100;\r\n\t1 1;\r\n\t1 1100;\r\n\t1 1];\r\nassert(isequal(equation_time(time),y_correct))\r\n\r\n%%\r\ntime = '2:38';\r\ny_correct = zeros(4,2);\r\nassert(isequal(equation_time(time),y_correct))\r\n\r\n%%\r\ntime = '5:15';\r\ny_correct = [0 0;\r\n\t0 0;\r\n\t1 1111;\r\n \t1 1001];\r\nassert(isequal(equation_time(time),y_correct))\r\n\r\n%%\r\ntime = '1:23';\r\ny_correct = [1 11;\r\n\t1 1000;\r\n\t0 0;\r\n \t0 0];\r\nassert(isequal(equation_time(time),y_correct))\r\n\r\n%%\r\ntime = '1:02';\r\ny_correct = zeros(4,2);\r\nassert(isequal(equation_time(time),y_correct))\r\n\r\n%%\r\ntime = '1:11';\r\ny_correct = [0 0;\r\n\t0 0;\r\n\t1 1111;\r\n \t1 1111];\r\nassert(isequal(equation_time(time),y_correct))\r\n\r\n%%\r\ntime = '2:11';\r\ny_correct = [1 1100;\r\n\t1 1;\r\n\t0 0;\r\n \t0 0];\r\nassert(isequal(equation_time(time),y_correct))","published":true,"deleted":false,"likes_count":3,"comments_count":0,"created_by":26769,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":79,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":45,"created_at":"2014-07-15T18:39:02.000Z","updated_at":"2026-01-15T14:29:10.000Z","published_at":"2014-07-15T18:39:02.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eMany times throughout the day can represent mathematical equations. In this problem, we focus on times that include the four basic operations (+,-,*,/). For example, 6:17 can be written as 6=1+7. Write a function that determines if the given time (restricted to three digits in 12-hour time, 1:00 to 9:59) is an equation time, and if so, which basic operation it uses. There are also four types of equations that are categorized here, and a given time can fit more than one category:\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"code\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003e\u003c![CDATA[ - equation written forward, \\\"=\\\" doesn't coincide with \\\":\\\" --\u003e add 1 to output (e.g., 2:35, 2+3=5)\\n\\n - equation written forward, \\\"=\\\" does coincide with \\\":\\\" -- \u003e add 100 to output (e.g., 2:53, 2=5-3)\\n\\n - equation written backward, \\\"=\\\" doesn't coincide with \\\":\\\" --\u003e add 10 to output (e.g., 3:26, 6=2*3)\\n\\n - equation written backward, \\\"=\\\" does coincide with \\\":\\\" --\u003e add 1000 to output (e.g., 4:28, 8/2=4)]]\u003e\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eNote that some of these combinations are tied to each other due to the commutative nature of + and * and the inverse relation of +,- and ,/. The output should be a 4x2 matrix with 0s or 1s in the first column dependent on whether each operation (+,-,*,/) is applicable to a given time and the totals in the second column. Examples include:\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003e4:22 | out = [1 1100; 1 1; 1 1100; 1 1]; since 4=2+2, 2+2=4; 4-2=2; 4=2*2, 2*2=4; 4/2=2.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003e5:15 | out = [0 0; 0 0; 1 1111; 1 1001]; since 5*1=5, 5=1*5, 5*1=5, 5=1*5; 5/1=5, 5/1=5.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eThis problem is related to\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:hyperlink w:docLocation=\\\"http://www.mathworks.com/matlabcentral/cody/problems/2431-power-times-of-the-day\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProblem 2431\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e and\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:hyperlink w:docLocation=\\\"http://www.mathworks.com/matlabcentral/cody/problems/2433-consecutive-equation-times-of-the-day\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProblem 2433\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\"},{\"partUri\":\"/matlab/output.xml\",\"contentType\":\"text/xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\" standalone=\\\"no\\\" ?\u003e\u003cembeddedOutputs\u003e\u003cmetaData\u003e\u003cevaluationState\u003emanual\u003c/evaluationState\u003e\u003clayoutState\u003ecode\u003c/layoutState\u003e\u003coutputStatus\u003eready\u003c/outputStatus\u003e\u003c/metaData\u003e\u003coutputArray type=\\\"array\\\"/\u003e\u003cregionArray type=\\\"array\\\"/\u003e\u003c/embeddedOutputs\u003e\"}]}"},{"id":2433,"title":"Consecutive Equation Times (of the day)","description":"Many times throughout the day can represent mathematical equations. In this problem, we focus on the largest consecutive run of equation times that include one of the four basic operations (+,-,*,/) or the power operator (^). Find the largest such consecutive run for a given range of input times (based on three-digit 12-hour times, 1:00 to 9:59). Return the first time stamp (string) and the number of consecutive points (integer, inclusive) for the maximum run (the first run if there is a tie).\r\n\r\nFor example, in the 2:07 to 2:29 time range, the answer is ['2:11' 3] since 2:10 has no equation, 2/1=1 (2:11), 2*1=2 (2:12), 2+1=3 (2:13) and 2:14 has no equation, and there are no such runs of four in that range.\r\n\r\nThis problem is related to \u003chttp://www.mathworks.com/matlabcentral/cody/problems/2431-power-times-of-the-day Problem 2431\u003e and \u003chttp://www.mathworks.com/matlabcentral/cody/problems/2432-equation-times-of-the-day  Problem 2432\u003e.","description_html":"\u003cp\u003eMany times throughout the day can represent mathematical equations. In this problem, we focus on the largest consecutive run of equation times that include one of the four basic operations (+,-,*,/) or the power operator (^). Find the largest such consecutive run for a given range of input times (based on three-digit 12-hour times, 1:00 to 9:59). Return the first time stamp (string) and the number of consecutive points (integer, inclusive) for the maximum run (the first run if there is a tie).\u003c/p\u003e\u003cp\u003eFor example, in the 2:07 to 2:29 time range, the answer is ['2:11' 3] since 2:10 has no equation, 2/1=1 (2:11), 2*1=2 (2:12), 2+1=3 (2:13) and 2:14 has no equation, and there are no such runs of four in that range.\u003c/p\u003e\u003cp\u003eThis problem is related to \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/2431-power-times-of-the-day\"\u003eProblem 2431\u003c/a\u003e and \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/2432-equation-times-of-the-day\"\u003eProblem 2432\u003c/a\u003e.\u003c/p\u003e","function_template":"function [t_s,num] = equation_times_run(times)\r\n t_s = '0:00';\r\n num = 0;\r\nend","test_suite":"%%\r\ntimes = {'1:00' '1:59'};\r\ny_correct = ['1:00' 24];\r\n[t_s,num] = equation_times_run(times);\r\nassert(isequal([t_s,num],y_correct))\r\n\r\n%%\r\ntimes = {'2:07' '2:29'};\r\ny_correct = ['2:11' 3];\r\n[t_s,num] = equation_times_run(times);\r\nassert(isequal([t_s,num],y_correct))\r\n\r\n%%\r\ntimes = {'3:03' '4:04'};\r\ny_correct = ['3:11' 4];\r\n[t_s,num] = equation_times_run(times);\r\nassert(isequal([t_s,num],y_correct))\r\n\r\n%%\r\ntimes = {'5:55' '7:11'};\r\ny_correct = ['6:15' 3];\r\n[t_s,num] = equation_times_run(times);\r\nassert(isequal([t_s,num],y_correct))\r\n\r\n%%\r\ntimes = {'7:17' '9:00'};\r\ny_correct = ['8:17' 3];\r\n[t_s,num] = equation_times_run(times);\r\nassert(isequal([t_s,num],y_correct))\r\n\r\n%%\r\ntimes = {'5:55' '9:00'};\r\ny_correct = ['6:15' 3];\r\n[t_s,num] = equation_times_run(times);\r\nassert(isequal([t_s,num],y_correct))\r\n\r\n%%\r\ntimes = {'1:00' '9:59'};\r\ny_correct = ['1:00' 24];\r\n[t_s,num] = equation_times_run(times);\r\nassert(isequal([t_s,num],y_correct))","published":true,"deleted":false,"likes_count":2,"comments_count":0,"created_by":26769,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":66,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":45,"created_at":"2014-07-15T19:39:50.000Z","updated_at":"2026-01-15T14:27:21.000Z","published_at":"2014-07-15T19:39:50.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eMany times throughout the day can represent mathematical equations. In this problem, we focus on the largest consecutive run of equation times that include one of the four basic operations (+,-,*,/) or the power operator (^). Find the largest such consecutive run for a given range of input times (based on three-digit 12-hour times, 1:00 to 9:59). Return the first time stamp (string) and the number of consecutive points (integer, inclusive) for the maximum run (the first run if there is a tie).\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eFor example, in the 2:07 to 2:29 time range, the answer is ['2:11' 3] since 2:10 has no equation, 2/1=1 (2:11), 2*1=2 (2:12), 2+1=3 (2:13) and 2:14 has no equation, and there are no such runs of four in that range.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eThis problem is related to\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:hyperlink w:docLocation=\\\"http://www.mathworks.com/matlabcentral/cody/problems/2431-power-times-of-the-day\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProblem 2431\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e and\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:hyperlink w:docLocation=\\\"http://www.mathworks.com/matlabcentral/cody/problems/2432-equation-times-of-the-day\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProblem 2432\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\"},{\"partUri\":\"/matlab/output.xml\",\"contentType\":\"text/xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\" standalone=\\\"no\\\" ?\u003e\u003cembeddedOutputs\u003e\u003cmetaData\u003e\u003cevaluationState\u003emanual\u003c/evaluationState\u003e\u003clayoutState\u003ecode\u003c/layoutState\u003e\u003coutputStatus\u003eready\u003c/outputStatus\u003e\u003c/metaData\u003e\u003coutputArray type=\\\"array\\\"/\u003e\u003cregionArray type=\\\"array\\\"/\u003e\u003c/embeddedOutputs\u003e\"}]}"}],"problem_search":{"errors":[],"problems":[{"id":2431,"title":"Power Times (of the day)","description":"Many times throughout the day can represent mathematical equations. In this problem, we focus on times that represent powers. For example, 8:23 can be written as 8=2^3. Write a function that determines if the given time (restricted to three digits in 12-hour time, 1:00 to 9:59) is a power time. There are four types that are categorized here, and a given time can fit more than one category:\r\n\r\n - equation written forward, \"=\" doesn't coincide with \":\" --\u003e add 1 to output (e.g., 2:38)\r\n\r\n - equation written forward, \"=\" does coincide with \":\" -- \u003e add 100 to output (e.g., 8:23)\r\n\r\n - equation written backward, \"=\" doesn't coincide with \":\" --\u003e add 10 to output (e.g., 3:28)\r\n\r\n - equation written backward, \"=\" does coincide with \":\" --\u003e add 1000 to output (e.g., 9:23)\r\n\r\nExamples of combination times include 4:22 (1100 since 4=2^2 and 2^2=4) and 1:31 (1001 since 1^3=1 and 1^3=1).\r\n\r\nThis problem is related to \u003chttp://www.mathworks.com/matlabcentral/cody/problems/2432-equation-times-of-the-day  Problem 2432\u003e and \u003chttp://www.mathworks.com/matlabcentral/cody/problems/2433-consecutive-equation-times-of-the-day Problem 2433\u003e.","description_html":"\u003cp\u003eMany times throughout the day can represent mathematical equations. In this problem, we focus on times that represent powers. For example, 8:23 can be written as 8=2^3. Write a function that determines if the given time (restricted to three digits in 12-hour time, 1:00 to 9:59) is a power time. There are four types that are categorized here, and a given time can fit more than one category:\u003c/p\u003e\u003cpre\u003e - equation written forward, \"=\" doesn't coincide with \":\" --\u0026gt; add 1 to output (e.g., 2:38)\u003c/pre\u003e\u003cpre\u003e - equation written forward, \"=\" does coincide with \":\" -- \u0026gt; add 100 to output (e.g., 8:23)\u003c/pre\u003e\u003cpre\u003e - equation written backward, \"=\" doesn't coincide with \":\" --\u0026gt; add 10 to output (e.g., 3:28)\u003c/pre\u003e\u003cpre\u003e - equation written backward, \"=\" does coincide with \":\" --\u0026gt; add 1000 to output (e.g., 9:23)\u003c/pre\u003e\u003cp\u003eExamples of combination times include 4:22 (1100 since 4=2^2 and 2^2=4) and 1:31 (1001 since 1^3=1 and 1^3=1).\u003c/p\u003e\u003cp\u003eThis problem is related to \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/2432-equation-times-of-the-day\"\u003eProblem 2432\u003c/a\u003e and \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/2433-consecutive-equation-times-of-the-day\"\u003eProblem 2433\u003c/a\u003e.\u003c/p\u003e","function_template":"function out = power_time(time)\r\n out = 0;\r\nend","test_suite":"%%\r\ntime = '2:38';\r\ny_correct = 1;\r\nassert(isequal(power_time(time),y_correct))\r\n\r\n%%\r\ntime = '8:23';\r\ny_correct = 100;\r\nassert(isequal(power_time(time),y_correct))\r\n\r\n%%\r\ntime = '3:28';\r\ny_correct = 10;\r\nassert(isequal(power_time(time),y_correct))\r\n\r\n%%\r\ntime = '9:23';\r\ny_correct = 1000;\r\nassert(isequal(power_time(time),y_correct))\r\n\r\n%%\r\ntime = '7:22';\r\ny_correct = 0;\r\nassert(isequal(power_time(time),y_correct))\r\n\r\n%%\r\ntime = '1:31';\r\ny_correct = 1001;\r\nassert(isequal(power_time(time),y_correct))\r\n\r\n%%\r\ntime = '4:22';\r\ny_correct = 1100;\r\nassert(isequal(power_time(time),y_correct))\r\n\r\n%%\r\ntime = '1:02';\r\ny_correct = 1000;\r\nassert(isequal(power_time(time),y_correct))\r\n\r\n%%\r\ntime = '4:12';\r\ny_correct = 0;\r\nassert(isequal(power_time(time),y_correct))\r\n\r\n%%\r\ntime = '5:15';\r\ny_correct = 1001;\r\nassert(isequal(power_time(time),y_correct))","published":true,"deleted":false,"likes_count":2,"comments_count":8,"created_by":26769,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":96,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":45,"created_at":"2014-07-15T18:00:06.000Z","updated_at":"2026-01-15T14:21:57.000Z","published_at":"2014-07-15T18:00:06.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eMany times throughout the day can represent mathematical equations. In this problem, we focus on times that represent powers. For example, 8:23 can be written as 8=2^3. Write a function that determines if the given time (restricted to three digits in 12-hour time, 1:00 to 9:59) is a power time. There are four types that are categorized here, and a given time can fit more than one category:\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"code\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003e\u003c![CDATA[ - equation written forward, \\\"=\\\" doesn't coincide with \\\":\\\" --\u003e add 1 to output (e.g., 2:38)\\n\\n - equation written forward, \\\"=\\\" does coincide with \\\":\\\" -- \u003e add 100 to output (e.g., 8:23)\\n\\n - equation written backward, \\\"=\\\" doesn't coincide with \\\":\\\" --\u003e add 10 to output (e.g., 3:28)\\n\\n - equation written backward, \\\"=\\\" does coincide with \\\":\\\" --\u003e add 1000 to output (e.g., 9:23)]]\u003e\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eExamples of combination times include 4:22 (1100 since 4=2^2 and 2^2=4) and 1:31 (1001 since 1^3=1 and 1^3=1).\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eThis problem is related to\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:hyperlink w:docLocation=\\\"http://www.mathworks.com/matlabcentral/cody/problems/2432-equation-times-of-the-day\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProblem 2432\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e and\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:hyperlink w:docLocation=\\\"http://www.mathworks.com/matlabcentral/cody/problems/2433-consecutive-equation-times-of-the-day\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProblem 2433\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\"},{\"partUri\":\"/matlab/output.xml\",\"contentType\":\"text/xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\" standalone=\\\"no\\\" ?\u003e\u003cembeddedOutputs\u003e\u003cmetaData\u003e\u003cevaluationState\u003emanual\u003c/evaluationState\u003e\u003clayoutState\u003ecode\u003c/layoutState\u003e\u003coutputStatus\u003eready\u003c/outputStatus\u003e\u003c/metaData\u003e\u003coutputArray type=\\\"array\\\"/\u003e\u003cregionArray type=\\\"array\\\"/\u003e\u003c/embeddedOutputs\u003e\"}]}"},{"id":2432,"title":"Equation Times (of the day)","description":"Many times throughout the day can represent mathematical equations. In this problem, we focus on times that include the four basic operations (+,-,*,/). For example, 6:17 can be written as 6=1+7. Write a function that determines if the given time (restricted to three digits in 12-hour time, 1:00 to 9:59) is an equation time, and if so, which basic operation it uses. There are also four types of equations that are categorized here, and a given time can fit more than one category:\r\n\r\n - equation written forward, \"=\" doesn't coincide with \":\" --\u003e add 1 to output (e.g., 2:35, 2+3=5)\r\n\r\n - equation written forward, \"=\" does coincide with \":\" -- \u003e add 100 to output (e.g., 2:53, 2=5-3)\r\n\r\n - equation written backward, \"=\" doesn't coincide with \":\" --\u003e add 10 to output (e.g., 3:26, 6=2*3)\r\n\r\n - equation written backward, \"=\" does coincide with \":\" --\u003e add 1000 to output (e.g., 4:28, 8/2=4)\r\n\r\nNote that some of these combinations are tied to each other due to the commutative nature of + and * and the inverse relation of +,- and **,/. The output should be a 4x2 matrix with 0s or 1s in the first column dependent on whether each operation (+,-,*,/) is applicable to a given time and the totals in the second column. Examples include: \r\n\r\n4:22 | out = [1 1100; 1 1; 1 1100; 1 1]; since 4=2+2, 2+2=4; 4-2=2; 4=2*2, 2*2=4; 4/2=2.\r\n\r\n5:15 | out = [0 0; 0 0; 1 1111; 1 1001]; since 5*1=5, 5=1*5, 5*1=5, 5=1*5; 5/1=5, 5/1=5.\r\n\r\nThis problem is related to \u003chttp://www.mathworks.com/matlabcentral/cody/problems/2431-power-times-of-the-day Problem 2431\u003e and \u003chttp://www.mathworks.com/matlabcentral/cody/problems/2433-consecutive-equation-times-of-the-day Problem 2433\u003e.","description_html":"\u003cp\u003eMany times throughout the day can represent mathematical equations. In this problem, we focus on times that include the four basic operations (+,-,*,/). For example, 6:17 can be written as 6=1+7. Write a function that determines if the given time (restricted to three digits in 12-hour time, 1:00 to 9:59) is an equation time, and if so, which basic operation it uses. There are also four types of equations that are categorized here, and a given time can fit more than one category:\u003c/p\u003e\u003cpre\u003e - equation written forward, \"=\" doesn't coincide with \":\" --\u0026gt; add 1 to output (e.g., 2:35, 2+3=5)\u003c/pre\u003e\u003cpre\u003e - equation written forward, \"=\" does coincide with \":\" -- \u0026gt; add 100 to output (e.g., 2:53, 2=5-3)\u003c/pre\u003e\u003cpre\u003e - equation written backward, \"=\" doesn't coincide with \":\" --\u0026gt; add 10 to output (e.g., 3:26, 6=2*3)\u003c/pre\u003e\u003cpre\u003e - equation written backward, \"=\" does coincide with \":\" --\u0026gt; add 1000 to output (e.g., 4:28, 8/2=4)\u003c/pre\u003e\u003cp\u003eNote that some of these combinations are tied to each other due to the commutative nature of + and * and the inverse relation of +,- and ,/. The output should be a 4x2 matrix with 0s or 1s in the first column dependent on whether each operation (+,-,*,/) is applicable to a given time and the totals in the second column. Examples include:\u003c/p\u003e\u003cp\u003e4:22 | out = [1 1100; 1 1; 1 1100; 1 1]; since 4=2+2, 2+2=4; 4-2=2; 4=2*2, 2*2=4; 4/2=2.\u003c/p\u003e\u003cp\u003e5:15 | out = [0 0; 0 0; 1 1111; 1 1001]; since 5*1=5, 5=1*5, 5*1=5, 5=1*5; 5/1=5, 5/1=5.\u003c/p\u003e\u003cp\u003eThis problem is related to \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/2431-power-times-of-the-day\"\u003eProblem 2431\u003c/a\u003e and \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/2433-consecutive-equation-times-of-the-day\"\u003eProblem 2433\u003c/a\u003e.\u003c/p\u003e","function_template":"function out = equation_time(time)\r\n out = 0;\r\nend","test_suite":"%%\r\ntime = '4:22';\r\ny_correct = [1 1100;\r\n\t1 1;\r\n\t1 1100;\r\n\t1 1];\r\nassert(isequal(equation_time(time),y_correct))\r\n\r\n%%\r\ntime = '2:38';\r\ny_correct = zeros(4,2);\r\nassert(isequal(equation_time(time),y_correct))\r\n\r\n%%\r\ntime = '5:15';\r\ny_correct = [0 0;\r\n\t0 0;\r\n\t1 1111;\r\n \t1 1001];\r\nassert(isequal(equation_time(time),y_correct))\r\n\r\n%%\r\ntime = '1:23';\r\ny_correct = [1 11;\r\n\t1 1000;\r\n\t0 0;\r\n \t0 0];\r\nassert(isequal(equation_time(time),y_correct))\r\n\r\n%%\r\ntime = '1:02';\r\ny_correct = zeros(4,2);\r\nassert(isequal(equation_time(time),y_correct))\r\n\r\n%%\r\ntime = '1:11';\r\ny_correct = [0 0;\r\n\t0 0;\r\n\t1 1111;\r\n \t1 1111];\r\nassert(isequal(equation_time(time),y_correct))\r\n\r\n%%\r\ntime = '2:11';\r\ny_correct = [1 1100;\r\n\t1 1;\r\n\t0 0;\r\n \t0 0];\r\nassert(isequal(equation_time(time),y_correct))","published":true,"deleted":false,"likes_count":3,"comments_count":0,"created_by":26769,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":79,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":45,"created_at":"2014-07-15T18:39:02.000Z","updated_at":"2026-01-15T14:29:10.000Z","published_at":"2014-07-15T18:39:02.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eMany times throughout the day can represent mathematical equations. In this problem, we focus on times that include the four basic operations (+,-,*,/). For example, 6:17 can be written as 6=1+7. Write a function that determines if the given time (restricted to three digits in 12-hour time, 1:00 to 9:59) is an equation time, and if so, which basic operation it uses. There are also four types of equations that are categorized here, and a given time can fit more than one category:\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"code\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003e\u003c![CDATA[ - equation written forward, \\\"=\\\" doesn't coincide with \\\":\\\" --\u003e add 1 to output (e.g., 2:35, 2+3=5)\\n\\n - equation written forward, \\\"=\\\" does coincide with \\\":\\\" -- \u003e add 100 to output (e.g., 2:53, 2=5-3)\\n\\n - equation written backward, \\\"=\\\" doesn't coincide with \\\":\\\" --\u003e add 10 to output (e.g., 3:26, 6=2*3)\\n\\n - equation written backward, \\\"=\\\" does coincide with \\\":\\\" --\u003e add 1000 to output (e.g., 4:28, 8/2=4)]]\u003e\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eNote that some of these combinations are tied to each other due to the commutative nature of + and * and the inverse relation of +,- and ,/. The output should be a 4x2 matrix with 0s or 1s in the first column dependent on whether each operation (+,-,*,/) is applicable to a given time and the totals in the second column. Examples include:\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003e4:22 | out = [1 1100; 1 1; 1 1100; 1 1]; since 4=2+2, 2+2=4; 4-2=2; 4=2*2, 2*2=4; 4/2=2.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003e5:15 | out = [0 0; 0 0; 1 1111; 1 1001]; since 5*1=5, 5=1*5, 5*1=5, 5=1*5; 5/1=5, 5/1=5.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eThis problem is related to\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:hyperlink w:docLocation=\\\"http://www.mathworks.com/matlabcentral/cody/problems/2431-power-times-of-the-day\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProblem 2431\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e and\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:hyperlink w:docLocation=\\\"http://www.mathworks.com/matlabcentral/cody/problems/2433-consecutive-equation-times-of-the-day\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProblem 2433\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\"},{\"partUri\":\"/matlab/output.xml\",\"contentType\":\"text/xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\" standalone=\\\"no\\\" ?\u003e\u003cembeddedOutputs\u003e\u003cmetaData\u003e\u003cevaluationState\u003emanual\u003c/evaluationState\u003e\u003clayoutState\u003ecode\u003c/layoutState\u003e\u003coutputStatus\u003eready\u003c/outputStatus\u003e\u003c/metaData\u003e\u003coutputArray type=\\\"array\\\"/\u003e\u003cregionArray type=\\\"array\\\"/\u003e\u003c/embeddedOutputs\u003e\"}]}"},{"id":2433,"title":"Consecutive Equation Times (of the day)","description":"Many times throughout the day can represent mathematical equations. In this problem, we focus on the largest consecutive run of equation times that include one of the four basic operations (+,-,*,/) or the power operator (^). Find the largest such consecutive run for a given range of input times (based on three-digit 12-hour times, 1:00 to 9:59). Return the first time stamp (string) and the number of consecutive points (integer, inclusive) for the maximum run (the first run if there is a tie).\r\n\r\nFor example, in the 2:07 to 2:29 time range, the answer is ['2:11' 3] since 2:10 has no equation, 2/1=1 (2:11), 2*1=2 (2:12), 2+1=3 (2:13) and 2:14 has no equation, and there are no such runs of four in that range.\r\n\r\nThis problem is related to \u003chttp://www.mathworks.com/matlabcentral/cody/problems/2431-power-times-of-the-day Problem 2431\u003e and \u003chttp://www.mathworks.com/matlabcentral/cody/problems/2432-equation-times-of-the-day  Problem 2432\u003e.","description_html":"\u003cp\u003eMany times throughout the day can represent mathematical equations. In this problem, we focus on the largest consecutive run of equation times that include one of the four basic operations (+,-,*,/) or the power operator (^). Find the largest such consecutive run for a given range of input times (based on three-digit 12-hour times, 1:00 to 9:59). Return the first time stamp (string) and the number of consecutive points (integer, inclusive) for the maximum run (the first run if there is a tie).\u003c/p\u003e\u003cp\u003eFor example, in the 2:07 to 2:29 time range, the answer is ['2:11' 3] since 2:10 has no equation, 2/1=1 (2:11), 2*1=2 (2:12), 2+1=3 (2:13) and 2:14 has no equation, and there are no such runs of four in that range.\u003c/p\u003e\u003cp\u003eThis problem is related to \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/2431-power-times-of-the-day\"\u003eProblem 2431\u003c/a\u003e and \u003ca href = \"http://www.mathworks.com/matlabcentral/cody/problems/2432-equation-times-of-the-day\"\u003eProblem 2432\u003c/a\u003e.\u003c/p\u003e","function_template":"function [t_s,num] = equation_times_run(times)\r\n t_s = '0:00';\r\n num = 0;\r\nend","test_suite":"%%\r\ntimes = {'1:00' '1:59'};\r\ny_correct = ['1:00' 24];\r\n[t_s,num] = equation_times_run(times);\r\nassert(isequal([t_s,num],y_correct))\r\n\r\n%%\r\ntimes = {'2:07' '2:29'};\r\ny_correct = ['2:11' 3];\r\n[t_s,num] = equation_times_run(times);\r\nassert(isequal([t_s,num],y_correct))\r\n\r\n%%\r\ntimes = {'3:03' '4:04'};\r\ny_correct = ['3:11' 4];\r\n[t_s,num] = equation_times_run(times);\r\nassert(isequal([t_s,num],y_correct))\r\n\r\n%%\r\ntimes = {'5:55' '7:11'};\r\ny_correct = ['6:15' 3];\r\n[t_s,num] = equation_times_run(times);\r\nassert(isequal([t_s,num],y_correct))\r\n\r\n%%\r\ntimes = {'7:17' '9:00'};\r\ny_correct = ['8:17' 3];\r\n[t_s,num] = equation_times_run(times);\r\nassert(isequal([t_s,num],y_correct))\r\n\r\n%%\r\ntimes = {'5:55' '9:00'};\r\ny_correct = ['6:15' 3];\r\n[t_s,num] = equation_times_run(times);\r\nassert(isequal([t_s,num],y_correct))\r\n\r\n%%\r\ntimes = {'1:00' '9:59'};\r\ny_correct = ['1:00' 24];\r\n[t_s,num] = equation_times_run(times);\r\nassert(isequal([t_s,num],y_correct))","published":true,"deleted":false,"likes_count":2,"comments_count":0,"created_by":26769,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":66,"test_suite_updated_at":null,"rescore_all_solutions":false,"group_id":45,"created_at":"2014-07-15T19:39:50.000Z","updated_at":"2026-01-15T14:27:21.000Z","published_at":"2014-07-15T19:39:50.000Z","restored_at":null,"restored_by":null,"spam":false,"simulink":false,"admin_reviewed":false,"description_opc":"{\"relationships\":[{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/document\",\"targetMode\":\"\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"targetMode\":\"\",\"relationshipId\":\"rId2\",\"target\":\"/matlab/output.xml\"}],\"parts\":[{\"partUri\":\"/matlab/document.xml\",\"relationship\":[],\"contentType\":\"application/vnd.mathworks.matlab.code.document+xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\"?\u003e\\n\u003cw:document xmlns:w=\\\"http://schemas.openxmlformats.org/wordprocessingml/2006/main\\\"\u003e\u003cw:body\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eMany times throughout the day can represent mathematical equations. In this problem, we focus on the largest consecutive run of equation times that include one of the four basic operations (+,-,*,/) or the power operator (^). Find the largest such consecutive run for a given range of input times (based on three-digit 12-hour times, 1:00 to 9:59). Return the first time stamp (string) and the number of consecutive points (integer, inclusive) for the maximum run (the first run if there is a tie).\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eFor example, in the 2:07 to 2:29 time range, the answer is ['2:11' 3] since 2:10 has no equation, 2/1=1 (2:11), 2*1=2 (2:12), 2+1=3 (2:13) and 2:14 has no equation, and there are no such runs of four in that range.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eThis problem is related to\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:hyperlink w:docLocation=\\\"http://www.mathworks.com/matlabcentral/cody/problems/2431-power-times-of-the-day\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProblem 2431\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e and\u003c/w:t\u003e\u003c/w:r\u003e\u003cw:r\u003e\u003cw:t\u003e \u003c/w:t\u003e\u003c/w:r\u003e\u003cw:hyperlink w:docLocation=\\\"http://www.mathworks.com/matlabcentral/cody/problems/2432-equation-times-of-the-day\\\"\u003e\u003cw:r\u003e\u003cw:t\u003eProblem 2432\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:hyperlink\u003e\u003cw:r\u003e\u003cw:t\u003e.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003c/w:body\u003e\u003c/w:document\u003e\"},{\"partUri\":\"/matlab/output.xml\",\"contentType\":\"text/xml\",\"content\":\"\u003c?xml version=\\\"1.0\\\" encoding=\\\"UTF-8\\\" standalone=\\\"no\\\" ?\u003e\u003cembeddedOutputs\u003e\u003cmetaData\u003e\u003cevaluationState\u003emanual\u003c/evaluationState\u003e\u003clayoutState\u003ecode\u003c/layoutState\u003e\u003coutputStatus\u003eready\u003c/outputStatus\u003e\u003c/metaData\u003e\u003coutputArray type=\\\"array\\\"/\u003e\u003cregionArray type=\\\"array\\\"/\u003e\u003c/embeddedOutputs\u003e\"}]}"}],"term":"tag:\"minute\"","current_player_id":null,"fields":[{"name":"page","type":"integer","callback":null,"default":1,"directive":null,"facet":null,"facet_method":"and","operator":null,"param":null,"static":null,"prepend":true},{"name":"per_page","type":"integer","callback":null,"default":50,"directive":null,"facet":null,"facet_method":"and","operator":null,"param":null,"static":null,"prepend":true},{"name":"sort","type":"string","callback":null,"default":null,"directive":null,"facet":null,"facet_method":"and","operator":null,"param":null,"static":null,"prepend":true},{"name":"body","type":"text","callback":null,"default":"*:*","directive":null,"facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":false},{"name":"group","type":"string","callback":null,"default":null,"directive":"group","facet":true,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"difficulty_rating_bin","type":"string","callback":null,"default":null,"directive":"difficulty_rating_bin","facet":true,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"id","type":"integer","callback":null,"default":null,"directive":"id","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"tag","type":"string","callback":null,"default":null,"directive":"tag","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"product","type":"string","callback":null,"default":null,"directive":"product","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"created_at","type":"timeframe","callback":{},"default":null,"directive":"created_at","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"profile_id","type":"integer","callback":null,"default":null,"directive":"author_id","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"created_by","type":"string","callback":null,"default":null,"directive":"author","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"player_id","type":"integer","callback":null,"default":null,"directive":"solver_id","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"player","type":"string","callback":null,"default":null,"directive":"solver","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"solvers_count","type":"integer","callback":null,"default":null,"directive":"solvers_count","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"comments_count","type":"integer","callback":null,"default":null,"directive":"comments_count","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"likes_count","type":"integer","callback":null,"default":null,"directive":"likes_count","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"leader_id","type":"integer","callback":null,"default":null,"directive":"leader_id","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true},{"name":"leading_solution","type":"integer","callback":null,"default":null,"directive":"leading_solution","facet":null,"facet_method":"and","operator":null,"param":"term","static":null,"prepend":true}],"filters":[{"name":"asset_type","type":"string","callback":null,"default":null,"directive":null,"facet":null,"facet_method":"and","operator":null,"param":null,"static":"\"cody:problem\"","prepend":true},{"name":"profile_id","type":"integer","callback":{},"default":null,"directive":null,"facet":null,"facet_method":"and","operator":null,"param":"author_id","static":null,"prepend":true}],"query":{"params":{"per_page":50,"term":"tag:\"minute\"","current_player":null,"sort":"map(difficulty_value,0,0,999) 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