Problem:
Score : 100 points

Problem Statement

You are given two integers A and B as the input. Output the value of A + B.

However, if A + B is 10 or greater, output error instead.

Constraints

A and B are integers.

1 ≤ A, B ≤ 9

Input

Input is given from Standard Input in the following format:

A B

Output

If A + B is 10 or greater, print the string error (case-sensitive); otherwise, print the value of A + B.

Sample Input 1

6 3

Sample Output 1

9

Sample Input 2

6 4

Sample Output 2

error

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;

class Program
{
    static void Main(string[] args)
    {
        new Magatro().Solve();
    }
}

class Magatro
{
    private int A, B;
    public void Solve()
    {
        var line = Console.ReadLine().Split(' ');
        A = int.Parse(line[0]);
        B = int.Parse(line[1]);
        int ans = A + B;
        if (ans < 10)
        {
            Console.WriteLine(ans);
        }
        else
        {
            Console.WriteLine("error");
        }
    }
}