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 {
  def main(args: Array[String]): Unit = {
    val str = io.StdIn.readLine().split(' ').map(_.toInt)
    val a = str(0)
    val b = str(1)
    println(if ((a+b)>=10) "error"else (a+b).toString)
  }

  def judge(a: Int, b: Int): String = {
    if (a + b < 10) {
      (a + b).toString
    } else {
      "error"
    }
  }
}