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 Rust (1.42.0) (judge verdict: Accepted)

fn main() {
	proconio::input!{
		a: usize,
		b: usize,
	}

	let sum = a+b;
	if sum >= 10 {
		println!("error");
	}
	else {
		println!("{}", sum);
	}
}