Problem:
Score : 100 points

Problem Statement

Joisino wants to evaluate the formula "A op B".
Here, A and B are integers, and the binary operator op is either + or -.
Your task is to evaluate the formula instead of her.

Constraints

1≦A,B≦10^9

op is either + or -.

Input

The input is given from Standard Input in the following format:

A op B

Output

Evaluate the formula and print the result.

Sample Input 1

1 + 2

Sample Output 1

3

Since 1 + 2 = 3, the output should be 3.

Sample Input 2

5 - 7

Sample Output 2

-2

Solution in C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Satoshi
{
	class Program
	{
		public static void Main(string[] args)
		{
			string[] s = Console.ReadLine().Split(' ');
			int a = int.Parse(s[0]);
			int b = int.Parse(s[2]);
			int ans = 0;
			switch (s[1])
			{
				case "+":
					ans = a + b;
					break;
				case "-":
					ans = a - b;
					break;
			}
			Console.WriteLine(ans);
		}
	}
}