#include <iostream>
using namespace std;
int main() {
    setlocale(LC_ALL, "Russian");
    int a;
    int b;
    int opperation;
    int& RfaO = opperation;
    cout << "Enter a :" << endl;
    cin >> a;
    cout << "Enter b :" << endl;
    cin >> b;
    cout << "Вот список доступных операций:  1. Сумма; 2. Разница; 3. Умножение; 4. Деление; 5. Остаток от деления :" << endl;

    cout << "Enter opperation :" << endl;
    cin >> RfaO;

    switch (RfaO) {
    case '1':
        cout << "a + b = " << a + b << '\n';
        break;
    case '2':
        cout << "a - b = " << a - b << '\n';
        break;

    case '3':
        cout << "a * b = " << a * b << '\n';
        break;
    case '4':
        cout << "a / b = " << a / b << '\n';
        break;
    case '5':
        cout << "a % b = " << a % b << '\n';
        break;
    default:
        cout << "Error";

    }
}