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;
#define rp(i,n) for(int i=0;i<n;i++)
#define rep(i,m,n) for(int i=m;i<=n;i++)
#define lrp(i,n) for(long long i=0;i<n;i++)
#define lrep(i,m,n) for(long long i=m;i<=n;i++)
#define ll long long
#define sort(a) sort(a.begin(),a.end())
#define reverse(a) reverse(a.begin(),a.end())
#define vi vector<int>
#define vl vector<long long>
#define pb push_back
#define abs(a,b) (a-b>0?a-b:b-a)
#define size size()

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