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<bits/stdc++.h>
using namespace std;
 
typedef long long ll;
typedef vector<pair<ll, ll>> pll;
 
#define mod 1000000007
#define all(x) (x).begin(), (x).end()
#define pb push_back
#define popcount(x) __builtin_popcountll(x)
 
const long double PI = acos(-1);
 
ll gcd(ll a,ll b){return b ? gcd(b,a%b) : a;}
ll lcm(ll a,ll b){return a / gcd(a,b) * b;}
ll stringcount(string s, char c){return count(s.cbegin(), s.cend(), c);}
bool isInteger(double x){return floor(x) == x;}

int main(){
  ios::sync_with_stdio(false);
  cin.tie(0);
  
  ll a, b;
  cin >> a >> b;
  if(a + b < 10) cout << a+b << endl;
  else cout << "error" << endl;
  return 0;
}