---

#include <iostream>

int sum(int a, int b)
{
    return a + b;
}

int minus(int a, int b)
{
    return a - b;
}

int multiply(int a, int b)
{
    return a * b;
}

int divide(int a, int b)
{
    return a / b;
}

int main()
{
    int a, b;
    char choose;

    std::cout << "1 - Умножение\n";
    std::cout << "2 - Деление\n";
    std::cout << "3 - Сложение\n";
    std::cout << "4 - Вычитание\n";
    std::cout << "0 - Выход\n";

    std::cin >> choose;

    if (choose == '1')
    {
        std::cin >> a >> b;
        std::cout << multiply(a, b);
    }
    else if (choose == '2')
    {
        std::cin >> a >> b;
        std::cout << divide(a, b);
    }
    else if (choose == '3')
    {
        std::cin >> a >> b;
        std::cout << sum(a, b);
    }
    else if (choose == '4')
    {
        std::cin >> a >> b;
        std::cout << minus(a, b);
    }

    return 0;
}
``