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++14 (GCC 5.4.1) (judge verdict: Accepted)

# include <iostream>
# include <algorithm>
# include <vector>
# include <string>
# include <set>
# include <cmath>
# include <iomanip>
# include <functional>

using namespace std;

int main() {
	int a, b;
	cin >> a >> b;
	if (a + b >= 10) {
		cout << "error" << endl;
	}
	else {
		cout << a + b << endl;
	}
}