using System;

​

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

    }

}

#include<iostream>

using 

​

namespace std ; 

    int main(void)

    {

        float ch1, ch2, res;

        char sim;

        cout << "Ââåäèòå äâà ÷èñëà ÷åðåç ïðîáåë: \n";

        cin >> ch1 >> ch2;

        cout << "Ââåäèòå ñèìâîë îïåðàöèè: \n";

        cin >> sim;

        switch (sim)

        {

            case '*':

                res = ch1 * ch2;

                break;

            case '/':

                res = ch1 / ch2;

                break;

            case '-':

                res = ch1 - ch2;

                break;

            case '+':

                res = ch1 + ch2;

                break;

        }

​

        cout << ch1 << sim << ch2 << "=" << res << endl;

        system("pause");

        return 0;

    }