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 Rust (1.15.1) (judge verdict: Accepted)


#![allow(unused)]

use std::cmp;
use std::io::{self, BufRead};
use std::iter;

macro_rules! destruct_ {
  ($e: expr, ()) => (
    assert!($e.next().is_none())
  );
  ($e: expr, ($arg: ident, $( $args: ident, )*)) => (
    $arg = $e.next().unwrap();
    destruct_!($e, ($($args,)*))
  );
  ($e: expr, ($arg: ident $(, $args: ident )*)) => (
    $arg = $e.next().unwrap();
    destruct_!($e, ($($args,)*))
  );
}

macro_rules! into {
  ($e: expr, $($name: ident)*) => {
    let mut iter = $e.into_iter();
    destruct_!(iter, ($($name)*));
  }
}

macro_rules! get {
  ($i: ident) => (
    let stdin = io::stdin();
    let mut $i = Vec::new();
    for line in stdin.lock().lines() {
      $i.push(
        line
          .unwrap()
          .split_whitespace()
          .map(|a| a.parse().unwrap())
          .collect()
      );
    }
  )
}

macro_rules! p {
  ($a: expr) => (
    println!("{}", $a);
  )
}

macro_rules! pp {
  ($a: expr) => (
    println!("{:?}", $a);
  )
}

fn main() {
  let mut args: Vec<Vec<i32>>;
  let mut ab: Vec<i32>;
  get!(args);
  into!(args, ab);

  let c = ab[0] + ab[1];
  if 10 <= c {
    p!("error");
  }
  else {
    p!(c);
  }
}