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: Runtime Error)

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

namespace ABC063A
{
	class Program
	{
		static void Main(string[] args)
		{
			int a, b, s;
			s = 10;
			a = int.Parse(Console.ReadLine());
			b = int.Parse(Console.ReadLine());
			if (s > (a + b))
			{
				Console.WriteLine("a+b");
			}
			else
			{
				Console.WriteLine("error");

				Console.ReadKey();
			}
		}
	}
}