LeetCode 744. Find Smallest Letter Greater Than Target (时间复杂度O（n）)

题目

太简单了，直接上代码：

class Solution {
public:
    char nextGreatestLetter(vector<char>& letters, char target) {
        int n = letters.size();
        int a[] = {};
        for(int i = ;i < n; ++i){
            a[letters[i]-'a']++;
        }
        for(int i = (target-'a'+)%; ; i++,i%=){
            if(a[i] > ) return (char)(i + 'a');
        }
    }
};