问题
给定一个字符串数组，将数组内元素进行反转。需在当前数组中原地交换。
输入："h","e","l","l","o"
输出："o","l","l","e","h"
思路
双指针。
定义一个指针left指向数组头部
定义一个指针right指向数组尾部
left不断自增，right不断自减。当left小于right时，则交换指针在数组内对应元素。
image.png
实现
public class ReverseString {
public static void main(String[] args) {
String[] chars = new String[]{"h","e","l","l","o"};
String[] result = doubleIndex(chars);
System.out.println(Arrays.toString(result));
}
//双指针
private static String[] doubleIndex(String[] chars) {
int length = chars.length;
int left = 0;
int right = length-1;
while (left < right){
doubleIndexSwap(chars,left++,right--);
}
return chars;
}
private static void doubleIndexSwap(String[] chars, int left, int right) {
String temp = chars[left];
chars[left] = chars[right];
chars[right] = temp;
}
}
image.png
