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 Scala (2.11.7) (judge verdict: Accepted)

object Main extends App {
    val a = scala.io.StdIn.readLine().split(" ").map(_.toInt)
    val x = a(0)
    val y = a(1)
    val ret = if (x+y<10) x+y else "error" 
    println(ret)
}