leetcode-344-easy

Reverse String
思路一: 首尾互换

public void reverseString(char[] s) {
    int mid = s.length / 2;
    int begin = 0;
    int end = s.length - 1;
    while (begin < mid) {
        char t = s[begin];
        s[begin++] = s[end];
        s[end--] = t;
    }
}