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>
using namespace std;

int main() {
  int a, b;
  cin >> a >> b;
  int c = a + b;
  if (c < 10) cout << c << endl;
  else cout << "error" << endl;
  return 0;
}