Возводим все в квадрат

#include <iostream>
#include <string>
#include <map>
#include <vector>
#include <utility> // std::pair, std::get

/**
 * Возводим все в квадрат
 * vector, map, pair
 */

template <class Type>
Type Sqr(Type var) {
    return var * var;
}

template <class Type>
std::vector<Type> Sqr(std::vector<Type> vec) {
    for (auto &elem : vec) {
        elem = Sqr(elem);
    }
    return vec;
}

template <class First, class Second>
std::pair<First, Second> Sqr(std::pair<First, Second> pair) {
    std::get<0>(pair) = Sqr(std::get<0>(pair));
    std::get<1>(pair) = Sqr(std::get<1>(pair));
    return pair;
}

template <class First, class Second>
std::map<First, Second> Sqr(std::map<First, Second> map) {
    for (auto &elem : map) {
        elem.second = Sqr(elem.second);
    }
    return map;
}

int main() {
    std::vector<int> v = {1, 2, 3};
    std::cout << "vector:";
    for (int x : Sqr(v)) {
        std::cout << ' ' << x;
    }
    std::cout << std::endl;

    std::map<int, std::pair<int, int>> map_of_pairs = {
            {4, {2, 2}},
            {7, {4, 3}}
    };
    std::cout << "map of pairs:" << std::endl;
    for (const auto& x : Sqr(map_of_pairs)) {
        std::cout << x.first << ' ' << x.second.first << ' ' << x.second.second << std::endl;
    }

    return 0;
}