leetcode

0 class Solution {

1 public:

2 char nextGreatestLetter(vector<char> &letters, char target) {

3 if (target >= letters.back()) return letters.front();

4 int low = 0, high = letters.size() - 1;

5 target++;

6 while (low < high) {

7 int mid = low + (high - low) / 2;

8 if (letters[mid] == target)

9 return letters[mid];

10 else if (letters[mid] < target)

11 low = mid + 1;

12 else

13 high = mid;

14 }

15 return letters[high];

16 }

17 };