反转字符串 Reverse String
题目
翻转字符串
以下为详细说明：
Write a function that reverses a string. The input string is given as an array of characters char[].
Do not allocate extra space for another array, you must do this by modifying the input array in-place with O(1) extra memory.
You may assume all the characters consist of printable ascii characters.
Example 1:
Input: ["h","e","l","l","o"]
Output: ["o","l","l","e","h"]
Example 2:
Input: ["H","a","n","n","a","h"]
Output: ["h","a","n","n","a","H"]
思路&题解
public void reverseString(char[] s) {
if(s.length<=1){
return;
}
int mid = s.length/2;
int maxIndex = s.length-1;
for(int i = 0; i<mid;i++){
char tmp = s[i];
s[i] = s[maxIndex-i];
s[maxIndex-i] = tmp;
}
}