不使用第三个变量来交换连个数据

#include <iostream>

 using namespace std;
int a = 3;
 
int b = 4; 



//a = a ^ b; 

//b = a ^ b; 

//a = a ^ b; 



a = a + b; 

b = a - b;   

a = a - b ;   



cout << a <<endl; 

cout << b << endl;