55. (791) Custom Sort String - Leetcode.cpp

/*
You are given two strings order and s. All the characters of order are unique and were sorted in some custom order previously.

Permute the characters of s so that they match the order that order was sorted. More specifically, if a character x occurs before a character y in order, then x should occur before y in the permuted string.

Return any permutation of s that satisfies this property.
*/

class Solution {
public:
    string customSortString(string S, string T) {
        sort(T.begin(), T.end(),
             [&](char a, char b) { return S.find(a) < S.find(b); });
        return T;
    }
};