1
class Solution {
2
 public:
3
  void reverseString(vector<char> &s) {
4
    int i = 0;
5
    int j = s.size() - 1;
6

7
    while (i <= j) {
8
      char temp = s[i];
9
      s[i] = s[j];
10
      s[j] = temp;
11
      i++;
12
      j--;
13
    }
14
  }
15
};