{"group":{"id":1,"name":"Community","lockable":false,"created_at":"2012-01-18T18:02:15.000Z","updated_at":"2026-05-26T00:16:20.000Z","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":"2026-05-26T00:00:00.000Z","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":680,"title":"Hack not this Test Suite you will","description":"Another Hack 10000 Challenge.\r\n\r\nI am thinking of an integer between 1 and 10000.\r\n\r\nReturn a value between 1 and 10000.\r\n\r\nI may select my number before or after your selection and will not use your number in any way if it is selected first. If I select first I may throw out my first roll and use my second. I will not roll three times.\r\n\r\nI may randomize the random seed,rng (20-25), before both our numbers are selected but not between number selections.  I may skip randomizing in a test suite. The first test suite does not change rng.\r\n\r\nWarning: Foiling with isequal will lead to dire consequences.  Kudos to Qi.\r\n\r\nThis problem can be made impossible if rng(2^32) is used and I select first as there are then multiple solutions.\r\n\r\nEnjoy\r\n\r\n","description_html":"\u003cp\u003eAnother Hack 10000 Challenge.\u003c/p\u003e\u003cp\u003eI am thinking of an integer between 1 and 10000.\u003c/p\u003e\u003cp\u003eReturn a value between 1 and 10000.\u003c/p\u003e\u003cp\u003eI may select my number before or after your selection and will not use your number in any way if it is selected first. If I select first I may throw out my first roll and use my second. I will not roll three times.\u003c/p\u003e\u003cp\u003eI may randomize the random seed,rng (20-25), before both our numbers are selected but not between number selections.  I may skip randomizing in a test suite. The first test suite does not change rng.\u003c/p\u003e\u003cp\u003eWarning: Foiling with isequal will lead to dire consequences.  Kudos to Qi.\u003c/p\u003e\u003cp\u003eThis problem can be made impossible if rng(2^32) is used and I select first as there are then multiple solutions.\u003c/p\u003e\u003cp\u003eEnjoy\u003c/p\u003e","function_template":"function y = Good_Luck(x)\r\n  y = 1;\r\nend","test_suite":"%%\r\nme=randi(10000);\r\nchallenger=Good_Luck(1);\r\nassert(isequal(me,challenger))\r\n%%\r\nrandi(5);\r\nrandi(5);\r\ny=randi(5)+20;\r\nrng(y);\r\nchallenger=Good_Luck(1);\r\nif isequal(2,1)\r\n while true\r\n  % Binbin Qi gets a TimeOut\r\n end\r\nend\r\nme=randi(10000);\r\nassert(isequal(challenger,me))\r\n%%\r\nrandi(5);\r\ny=randi(5)+20;\r\nrng(y);\r\nme=randi(10000);\r\nchallenger=Good_Luck(1);\r\nassert(me==challenger)\r\n%%\r\nrandi(5);\r\ny=randi(5)+20;\r\nrng(y);\r\nrandi(10000);\r\nme=randi(10000);\r\nchallenger=Good_Luck(1);\r\nassert(isequal(me,challenger))\r\n%%\r\nrandi(5);randi(5);randi(5);\r\ny=randi(5)+20;\r\nrng(y);\r\nme=randi(10000);\r\nchallenger=Good_Luck(1);\r\nassert(isequal(me,challenger))\r\n%%\r\ny=randi(5);\r\nwhile y\u003c20\r\n y=y+randi(5);\r\nend\r\nrng(y);\r\nme=randi(10000);\r\nchallenger=Good_Luck(1);\r\nassert(me==challenger)\r\n%%\r\nrng(24);\r\nme=randi(10000);\r\nchallenger=Good_Luck(1);\r\nassert(me==challenger)\r\n%%\r\nrng(23);\r\nrandi(10000);\r\nme=randi(10000);\r\nchallenger=Good_Luck(1);\r\nassert(me==challenger)\r\n%%\r\nchallenger=Good_Luck(1);\r\nme=randi(10000);\r\nassert(challenger==me)\r\n%%\r\nme=randi(10000);\r\nchallenger=Good_Luck(1);\r\nassert(isequal(me,challenger))\r\n%%\r\nrng(25);\r\nchallenger=Good_Luck(1);\r\nme=randi(10000);\r\nassert(isequal(me,challenger))","published":true,"deleted":false,"likes_count":0,"comments_count":2,"created_by":3097,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":18,"test_suite_updated_at":"2012-05-12T00:51:14.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2012-05-11T22:46:32.000Z","updated_at":"2026-05-26T03:35:26.000Z","published_at":"2012-05-12T00:51:14.000Z","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\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"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\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\u003eAnother Hack 10000 Challenge.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eI am thinking of an integer between 1 and 10000.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eReturn a value between 1 and 10000.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eI may select my number before or after your selection and will not use your number in any way if it is selected first. If I select first I may throw out my first roll and use my second. I will not roll three times.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eI may randomize the random seed,rng (20-25), before both our numbers are selected but not between number selections. I may skip randomizing in a test suite. The first test suite does not change rng.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eWarning: Foiling with isequal will lead to dire consequences. Kudos to Qi.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eThis problem can be made impossible if rng(2^32) is used and I select first as there are then multiple solutions.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eEnjoy\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":{"problems":[{"id":680,"title":"Hack not this Test Suite you will","description":"Another Hack 10000 Challenge.\r\n\r\nI am thinking of an integer between 1 and 10000.\r\n\r\nReturn a value between 1 and 10000.\r\n\r\nI may select my number before or after your selection and will not use your number in any way if it is selected first. If I select first I may throw out my first roll and use my second. I will not roll three times.\r\n\r\nI may randomize the random seed,rng (20-25), before both our numbers are selected but not between number selections.  I may skip randomizing in a test suite. The first test suite does not change rng.\r\n\r\nWarning: Foiling with isequal will lead to dire consequences.  Kudos to Qi.\r\n\r\nThis problem can be made impossible if rng(2^32) is used and I select first as there are then multiple solutions.\r\n\r\nEnjoy\r\n\r\n","description_html":"\u003cp\u003eAnother Hack 10000 Challenge.\u003c/p\u003e\u003cp\u003eI am thinking of an integer between 1 and 10000.\u003c/p\u003e\u003cp\u003eReturn a value between 1 and 10000.\u003c/p\u003e\u003cp\u003eI may select my number before or after your selection and will not use your number in any way if it is selected first. If I select first I may throw out my first roll and use my second. I will not roll three times.\u003c/p\u003e\u003cp\u003eI may randomize the random seed,rng (20-25), before both our numbers are selected but not between number selections.  I may skip randomizing in a test suite. The first test suite does not change rng.\u003c/p\u003e\u003cp\u003eWarning: Foiling with isequal will lead to dire consequences.  Kudos to Qi.\u003c/p\u003e\u003cp\u003eThis problem can be made impossible if rng(2^32) is used and I select first as there are then multiple solutions.\u003c/p\u003e\u003cp\u003eEnjoy\u003c/p\u003e","function_template":"function y = Good_Luck(x)\r\n  y = 1;\r\nend","test_suite":"%%\r\nme=randi(10000);\r\nchallenger=Good_Luck(1);\r\nassert(isequal(me,challenger))\r\n%%\r\nrandi(5);\r\nrandi(5);\r\ny=randi(5)+20;\r\nrng(y);\r\nchallenger=Good_Luck(1);\r\nif isequal(2,1)\r\n while true\r\n  % Binbin Qi gets a TimeOut\r\n end\r\nend\r\nme=randi(10000);\r\nassert(isequal(challenger,me))\r\n%%\r\nrandi(5);\r\ny=randi(5)+20;\r\nrng(y);\r\nme=randi(10000);\r\nchallenger=Good_Luck(1);\r\nassert(me==challenger)\r\n%%\r\nrandi(5);\r\ny=randi(5)+20;\r\nrng(y);\r\nrandi(10000);\r\nme=randi(10000);\r\nchallenger=Good_Luck(1);\r\nassert(isequal(me,challenger))\r\n%%\r\nrandi(5);randi(5);randi(5);\r\ny=randi(5)+20;\r\nrng(y);\r\nme=randi(10000);\r\nchallenger=Good_Luck(1);\r\nassert(isequal(me,challenger))\r\n%%\r\ny=randi(5);\r\nwhile y\u003c20\r\n y=y+randi(5);\r\nend\r\nrng(y);\r\nme=randi(10000);\r\nchallenger=Good_Luck(1);\r\nassert(me==challenger)\r\n%%\r\nrng(24);\r\nme=randi(10000);\r\nchallenger=Good_Luck(1);\r\nassert(me==challenger)\r\n%%\r\nrng(23);\r\nrandi(10000);\r\nme=randi(10000);\r\nchallenger=Good_Luck(1);\r\nassert(me==challenger)\r\n%%\r\nchallenger=Good_Luck(1);\r\nme=randi(10000);\r\nassert(challenger==me)\r\n%%\r\nme=randi(10000);\r\nchallenger=Good_Luck(1);\r\nassert(isequal(me,challenger))\r\n%%\r\nrng(25);\r\nchallenger=Good_Luck(1);\r\nme=randi(10000);\r\nassert(isequal(me,challenger))","published":true,"deleted":false,"likes_count":0,"comments_count":2,"created_by":3097,"edited_by":null,"edited_at":null,"deleted_by":null,"deleted_at":null,"solvers_count":18,"test_suite_updated_at":"2012-05-12T00:51:14.000Z","rescore_all_solutions":false,"group_id":1,"created_at":"2012-05-11T22:46:32.000Z","updated_at":"2026-05-26T03:35:26.000Z","published_at":"2012-05-12T00:51:14.000Z","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\",\"relationshipId\":\"rId1\",\"target\":\"/matlab/document.xml\"},{\"relationshipType\":\"http://schemas.mathworks.com/matlab/code/2013/relationships/output\",\"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\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\u003eAnother Hack 10000 Challenge.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eI am thinking of an integer between 1 and 10000.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eReturn a value between 1 and 10000.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eI may select my number before or after your selection and will not use your number in any way if it is selected first. If I select first I may throw out my first roll and use my second. I will not roll three times.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eI may randomize the random seed,rng (20-25), before both our numbers are selected but not between number selections. I may skip randomizing in a test suite. The first test suite does not change rng.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eWarning: Foiling with isequal will lead to dire consequences. Kudos to Qi.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eThis problem can be made impossible if rng(2^32) is used and I select first as there are then multiple solutions.\u003c/w:t\u003e\u003c/w:r\u003e\u003c/w:p\u003e\u003cw:p\u003e\u003cw:pPr\u003e\u003cw:pStyle w:val=\\\"text\\\"/\u003e\u003cw:jc w:val=\\\"left\\\"/\u003e\u003c/w:pPr\u003e\u003cw:r\u003e\u003cw:t\u003eEnjoy\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\"}]}"}],"errors":[],"facets":[[],[{"value":"medium","count":1,"selected":false}]],"term":"tag:\"hack rng randi\"","page":1,"per_page":50,"sort":"map(difficulty_value,0,0,999) asc"}}