using System;
public class Program
{
public static void Main()
int a = int.Parse(Console.ReadLine());
int b = int.Parse(Console.ReadLine());
int choise = int.Parse(Console.ReadLine());
switch(choise)
case 1: Console.WriteLine(a + b);
break;
case 2: Console.WriteLine(a - b);
case 3: Console.WriteLine(a*b);
}