Modular Cubes, part 1
This problem is simple. But pure brute force is not an option. I checked my old code, I kept a list of "possible solutions" and used something like bigInteger to do the modulo work since the numbers are too big. It only takes 17 ms, not too bad!
This time, I tried to avoid using bigIntegers since most of the problems with a number greater than 150 may be solved without the help of GMP. I found there is a better solution which used the famous Chinese Remainder Theorem. The problem is extremely simple after one understand what is going on inside CRT. Quite a few other project euler problems also check one's understanding of CRT, this one being the simplest one. It is a good opportunity to learn CRT!
My code runs less than 10 ms.
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