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 5.4.1) (judge verdict: Runtime Error)

#include <stdio.h>

int main(void){
  long long int n, a, b, h[100000], i, max=0, right, left, mid, re;
  scanf("%lld%lld%lld", &n, &a, &b);
  for(i=0; i<n; ++i){
    scanf("%lld", &h[i]);
    if(h[i] > max) max = h[i];
  }
  right = max / b + 1;
  left = 0;
  while(right - left > 1){
    mid = (right + left)/2;
    re = 0;
    for(i=0; i<n; ++i){
      if(h[i] > mid*b){
	re += (h[i]-mid*b)%(a-b) ? (h[i]-mid*b)/(a-b)+1:(h[i]-mid*b)/(a-b);
      }  
    }
    if(re>=mid) left=mid+1;
    else right=mid-1;
  }
  printf("%lld\n", left);
  return 0;
}