将字符串中的字符反向排序；

#include <stdio.h>#include<string.h>void swap(char *p1,char *p2){char temp = *p1;*p1 = *p2;*p2 = temp;}char * reverse_string(char * string){char *left = string;char *right = string + strlen(string)-1;while(left < right){swap(left,right);left ++;right --;}return string;}int main(){char arr[] = "abcdefg";reverse_string(arr);printf("%s\n",arr);return 0;}