LeetCode 3146 两个字符串的排列差

方法1：模拟 + 标记数组（哈希表）

class Solution {
    public int findPermutationDifference(String s, String t) {
        int[] idx = new int[26]; 
        int n = s.length(), ans = 0;
        for (int i = 1; i <= n; i++) {
            int idxS = s.charAt(i - 1) - 'a';
            int idxT = t.charAt(i - 1) - 'a';
            if (idx[idxS] != 0) 
                ans += i - idx[idxS];
            else
                idx[idxS] = i;
            if (idx[idxT] != 0)
                ans += i - idx[idxT];
            else
                idx[idxT] = i;
        }
        return ans;
    }
}

class Solution:
    def findPermutationDifference(self, s: str, t: str) -> int:
        idx = {ch : i for i, ch in enumerate(s)}
        return sum(abs(j - idx[ch]) for j, ch in enumerate(t))