// Given a string s consisting of distinct lowercase characters, determine its rank among all its permutations when those are arranged in lexicographically sorted order. // Note: The rank of a string ...

// Given two strings s1 and s2, return true if s2 contains a permutation of s1, or false otherwise. // In other words, return true if one of s1's permutations is the substring of s2.

- 1) to different permutations. A recursive approach (which is what I would use) would involve breaking the problem into isomorphic subproblems: to find all permutations of a string, find all ...