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: Wrong Answer)

using System;    
     
class sample15{    
    static void Main(string[] args){
        while(true){
            int  result;
            int[] calc_number = new int[2];
            string[] str_flagment = Console.ReadLine().Split(' '); 
            calc_number[0] = int.Parse(str_flagment[0]);
            string op = str_flagment[1];
            calc_number[1] = int.Parse(str_flagment[2]);
        
             //バリデーション
            if ( op == "?"){
                break;
            }else if(calc_number[0] < 0 || calc_number[1] < 0 || calc_number[0] > 20000 || calc_number[1] > 20000  ){ 
                    Console.WriteLine("値が範囲外です。"); 
                    Environment.Exit(0);
            }
        
            //opの値によって操作を変更
            switch(op){
                case "+":
                    result = calc_number[0] + calc_number[1];
                    Console.WriteLine(result);    
                    break;
                case "-":
                    result =  calc_number[0] - calc_number[1];
                    Console.WriteLine(result);
                    break;
                case "*":
                    result =  calc_number[0]* calc_number[1];
                    Console.WriteLine(result);
                    break;
                case "/":
                    if(calc_number[0] == 0 || calc_number[1] == 0){
                        Console.WriteLine("0を含め割り算を行うことはこの計算機ではできません。"); 
                        Environment.Exit(0);
                    }
        
                    result =  calc_number[0]/ calc_number[1];
                    Console.WriteLine(result);
                    break;
            }            
        }
            
    }
}