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>
#include <string>
#include <vector>
#include <climits>
#include <set>
#include <algorithm>
#include <unordered_map>
#include <queue>
#include <iomanip>
#include <map>
#include <utility>
#include <numeric>
#include <chrono>
#include <ctime>
#include <bitset>

#define rep(i,n) for(int i=0; i<(int)(n); i++)
#define P pair<int, int>
#define debug(x) cerr << #x << ": " << x << ", "
#define debugln(x) cerr << #x << ": " << x << '\n'

using namespace std;
using ll = long long;
const ll mod = 1e9+7;

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);

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