There are several ways to exchange two variables;

1. Borrow a temporary value to exchange two variables:

#include <stdio.h>
int main()
{
    
    
	int num1 = 5;
	int num2 = 8;
	int temp;//申请一个临时变量
	printf("num1和num2的值为%d %d\n", num1, num2);
	temp = num1;
	num1 = num2;
	num2 = temp;
	printf("num1和num2的值为%d %d\n", num1, num2);
	return 0;
}

2. Without temporary variables, exchange two variables:

**虽然不用借用临时变量，但是这种计算可能会导致越界
#include <stdio.h>
int main()
{
    
    
	int num1 = 5;
	int num2 = 8;
	printf("num1和num2的值为%d %d\n", num1, num2);
	num1 = num2 + num1;
	num2 = num1 - num2;
	num1 = num1 - num2;
	printf("num1和num2的值为%d %d\n", num1, num2);
	return 0;
}

3. Exchange two variables with XOR ^:

#include <stdio.h>
int main()
{
    
    
	int num1 = 5;
	int num2 = 8;
	printf("num1和num2的值为%d %d\n", num1, num2);
	num1 = num1^num2;
	num2=num1^num2;
	num1 = num1^num2;
	printf("num1和num2的值为%d %d\n", num1, num2);
	return 0;
}

4. Use pointers to exchange the values ​​of two variables:

#include<stdio.h>
int main()
{
    
    
	int num1 = 5;
	int num2 = 8;
	int temp;
	int *p1=&num1;
	int *p2 = &num2;
	printf("num1和num2的值为%d %d\n", num1, num2);
	printf("*p1和*p2的值为%d %d\n", *p1, *p2);
	temp = *p1;
	*p1 = *p2;
	*p2 = temp;
	printf("num1和num2的值为%d %d\n", num1, num2);
	printf("*p1和*p2的值为%d %d\n", *p1, *p2);
	return 0;
}