1、变量实现

	#include<iostream>
#include<assert.h>
char* Myoverturn(char* str, int n){
	assert(str);
	char tmp;
	char* left = str;
	char*  right = str + strlen(str) - 1;
          
        //while(left<right){                     //全部翻转                               
	while (n--){
		
			tmp = *left;
			*left = *right;
			*right = tmp;
			left++;
			right--;
	}
	return left;
}
int main(){

	char arr[] = "abcdefg";

	Myoverturn(arr, 2);

	printf("翻转后字符串：%s\n", arr);
	system("pause");

	return 0;
}
	

结果：

2、不使用变量

#include<iostream>
#include<assert.h>
char* Myoverturn(char* str, int n){
	assert(str);
	int len = strlen(str)-1;

	    //for (int i = 0; i < len - i; i++){                 //，去掉传入参数n,就可以全部翻转
		for (int i = 0; i < n;i++){

			str[i] = str[i] ^ str[len - i];
			str[len - i] = str[i] ^ str[len - i];
			str[i] = str[i] ^ str[len - i];
		}

	return str;
}

int main(){

	char arr[] = "abcdefg";
	Myoverturn(arr,1); 
	printf("翻转后字符串：%s\n", arr);
	system("pause");

	return 0;
}

 结果：