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;

namespace ConsoleApp43 {
    class Program {
        static void Main(string[] args) {
            var st = Console.ReadLine().Split(' ').Select(int.Parse).ToArray();

            int A = st[0];
            int B = st[1];

            if (A + B >= 10) {
                Console.WriteLine("error");
            } else {
                Console.WriteLine(A + B);
            }

        }
    }
}