pair 模板示例

#include <utility>
#include <cmath>
#include <iostream>
// 返回平方和平方根
std::pair<int, int> calculate(int x) {
    return {x+x,x*2};
}

int main() {
    std::pair<int,int> it = calculate(2);
    std::cout << "Square: " << it.first << ", Root: " << it.second << std::endl;    
}