# LeetCode - 0744. Find Smallest Letter Greater Than Target
### 題目網址：https://leetcode.com/problems/find-smallest-letter-greater-than-target/
###### tags: `LeetCode` `Easy` `二分搜尋法（Binary Search）`

/*
    -LeetCode format-
    Problem: 744. Find Smallest Letter Greater Than Target
    Difficulty: Easy
    
    by Inversionpeter
*/



class Solution {
public:
    char nextGreatestLetter(vector<char>& letters, char target) {
        vector <char>::iterator iter = upper_bound(letters.begin(), letters.end(), target);
        if (iter == letters.end())
            return letters[0];
        return *iter;
    }
};