What is radix sort?
a non-comparative integer sorting algorithm.
Related Puzzle: Single Number Problem
Puzzle: Given an array of integers, every element appears three times except for one. Find that single one.
A solution in relationship with radix sort:
Group some element into busket, and then do operation on them.
BTW, Another complicated solution :
A possible solution:
Solution one is much more general, cause’ it suites all find-n-same-element problem.