- Counting sort is a linear time sorting algorithm that sort in O(n+k) time when elements are in range from 1 to k.
- It can not be used because it will take O(n^2) which is worse than comparison based sorting algorithm.
- The idea of Radix Sort is to do digit by digit sort starting from least significant digit most most significant digit.
- Radix sort and Quick sort uses hardware caches more effectively.
- Also, Radix sort used counting sort as a subroutine and counting sort extra space to sort numbers.