Given an array. Find the minimum number of operation to sort the array. Operation: Take element from any position of the array and put it to end.

Given a string. Check if the string is a concatenation of any prefix of this string (any number of times concatenation is possible). If present then print the prefix, otherwise -1.

Hello Everyone!

Can u please tell me about the difficulty level of HackWithInfy question if you experienced last year.

Specify difficulty level in comparison with either Codeforces contest or Codechef long challenge.