The code is implemented in python without the use of itertools.permutations module, greater the list of numbers higher the time complexity as it is implemented with O(2^n) time complexity. It only takes the list of numbers not the R value. It only finds the permutation for given list of numbers assuming the R value as length of list. Input: Enter the list of numbers in the comma seperated form. Ex: 1 2 3 4 5