Problem:
Simple Calculator

Write a program which reads two integers a, b and an operator op, and then prints the value of a op b.

The operator op is '+', '-', '*' or '/' (sum, difference, product or quotient). The division should truncate any fractional part.

Input

The input consists of multiple datasets. Each dataset is given in the following format.

a op b

The input ends with a dataset where op = '?'. Your program should not process for this dataset.

Output

For each dataset, print the value in a line.

Constraints

0 ≤ a, b ≤ 20000

No divisions by zero are given.

Sample Input 1

1 + 2
56 - 18
13 * 2
100 / 10
27 + 81
0 ? 0

Sample Output 1

3
38
26
10
108

Solution in C# (judge verdict: Runtime Error)

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

namespace ITP1
{
    class ITP1_4_C
    {
        static void Main(string[] args)
        {
            int a, b;
            char op;
            List<char> dataSet;

            while (true)
            {
                dataSet = Console.ReadLine().Split().Select(char.Parse).ToList();

                // char to intは無い模様、これなら↑でstringのままでいい
                a = int.Parse(dataSet[0].ToString());
                op = dataSet[1];
                b = int.Parse(dataSet[2].ToString());

                switch (op)
                {
                    case '+':
                        Console.WriteLine(a + b);
                        break;
                    case '-':
                        Console.WriteLine(a - b);
                        break;
                    case '*':
                        Console.WriteLine(a * b);
                        break;
                    case '/':
                        Console.WriteLine(a / b);
                        break;
                    case '?':
                        Environment.Exit(0);
                        break;
                    default:
                        break;
                }
            }
        }
    }
}