Problem:
Score : 100 points

Problem Statement

Joisino wants to evaluate the formula "A op B".
Here, A and B are integers, and the binary operator op is either + or -.
Your task is to evaluate the formula instead of her.

Constraints

1≦A,B≦10^9

op is either + or -.

Input

The input is given from Standard Input in the following format:

A op B

Output

Evaluate the formula and print the result.

Sample Input 1

1 + 2

Sample Output 1

3

Since 1 + 2 = 3, the output should be 3.

Sample Input 2

5 - 7

Sample Output 2

-2

Solution in PHP (7.4.4) (judge verdict: Accepted)

<?php 
class Scanner {
    private $arr = [];
    private $count = 0;
    private $pointer = 0;
    public function next() {
        if($this->pointer >= $this->count) {
            $str = trim(fgets(STDIN));
            $this->arr = explode(' ', $str);
            $this->count = count($this->arr);
            $this->pointer = 0;
        }
        $result = $this->arr[$this->pointer];
        $this->pointer++;
        return $result;
    }
    public function hasNext() {
        return $this->pointer < $this->count;
    }
    public function nextInt() {
        return (int)$this->next();
    }
    public function nextString() {
        return (string)$this->next();
    }
    public function nextDouble() {
        return (double)$this->next();
    }
}

class out {
    public static function println($str = "") {
        echo $str . PHP_EOL;
    }
}

$sc = new Scanner();
$A = $sc->nextInt();
$OP = $sc->nextString();
$B = $sc->nextInt();


if ($OP == '+') {
    out::println($A  +  $B);
}else {
    out::println($A  -  $B);
}