Exchange of two numbers, the variable is not set

#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<stdlib.h>
//111 a
//011 b
//100 a
//111 b
//011 a
void Swap(int a, int b)
{
	a = a^b;
	b = a^b;
	a = a^b;
	printf("a=%d,b=%d\n", a, b);
}
void Swap1(int a, int b)
{
	a = a + b;
	b = a - b;
	a = a - b;
	printf("a=%d,b=%d\n", a, b);

}
int main()
{
	int a, b;
	printf("请输入两个数字！\n");
	scanf("%d %d", &a, &b);
	Swap(a,b);
	Swap1(a, b);
	system("pause");
	return 0;
}