May be I am wrong. But, are test 7 and 8 correct?
Looks like 7 and 8 should use fit(x), not fit(x,y).
Sorry for that. Fixed now.
Every test is correct. The problem with the circle packing algorithm is precision. Set the precision wrongly and we will miss a lot of circles (It was fun to revisit this kind of problem). And btw, the upper bound for circle packing in the plane is pi/sqrt(12) of the total area. Ignore the spheres in the question, it's a circle packing problem ("easy" version, since we already have the radii).
Swap the first and last columns
Given an unsigned integer x, find the largest y by rearranging the bits in x
Clock Hand Angle 1
Square Digits Number Chain Terminal Value (Inspired by Project Euler Problem 92)
Given a 4x4 matrix, swap the two middle columns
Pancake sorting - minimum flips.
Another colon problem
Arithmetic/geometric sequence, 50/50
Polite numbers. N-th polite number.
Choose a web site to get translated content where available and see local events and offers. Based on your location, we recommend that you select: .
You can also select a web site from the following list:
Select the China site (in Chinese or English) for best site performance. Other MathWorks country sites are not optimized for visits from your location.
Contact your local office