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 JavaScript (node.js v5.12) (judge verdict: Accepted)

function main(s) {
	s = s.split("\n")[0].split(" ").map(x => Number(x));
	console.log(s[0]+s[1]>=10?"error":String(s[0]+s[1]));
}
main(require("fs").readFileSync("/dev/stdin", "utf8"));