Given two strings s1 and s2, write a function to return true if s2 contains the permutation of s1. In other words, one of the first string's permutations is the substring of the second string ...

We know that a string can't be a permutation of another if their length aren't equal to solve this issue we use Sliding window, we know we have to check if s2 contains a permutation of s1. s1 & s2 ...