#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
int main() {
int a = 10, b = 25;
cout << "交换前: a = " << a << " | b = " << b << "\n";
swap(a, b);
cout << "交换后: a = " << a << " | b = " << b << "\n";
return 0;
}