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 (GCC 9.2.1) (judge verdict: Accepted)

#include <stdio.h>

int main(void) {
  int A, B;
  scanf("%d %d", &A, &B);
  if(1<=A<=9 && 1<=B<=9 && A+B<10){
    printf("%d\n", A+B);
  } else {
    printf ("error");
  }
  return 0;
}