程式語言 - LeetCode - C++ - 387. First Unique Character in a String



題目:


解答:

class Solution {
public:
    int firstUniqChar(string s) {
        vector<int> cnt(26, 0);

        for (char c : s) {
            cnt[c - 'a'] += 1;
        }

        for (int i = 0; i < s.size(); ++i) {
            if (cnt[s[i] - 'a'] == 1) {
                return i;
            }
        }

        return -1;
    }
};