Problem:
Score: 100 points

Problem Statement

Takahashi the Jumbo will practice golf.

His objective is to get a carry distance that is a multiple of K, while he can only make a carry distance of between A and B (inclusive).

If he can achieve the objective, print OK; if he cannot, print NG.

Constraints

All values in input are integers.

1 \leq A \leq B \leq 1000

1 \leq K \leq 1000

Input

Input is given from Standard Input in the following format:

K
A B

Output

If he can achieve the objective, print OK; if he cannot, print NG.

Sample Input 1

7
500 600

Sample Output 1

OK

Among the multiples of 7, for example, 567 lies between 500 and 600.

Sample Input 2

4
5 7

Sample Output 2

NG

No multiple of 4 lies between 5 and 7.

Sample Input 3

1
11 11

Sample Output 3

OK

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

<?php
while ($line = fgets(STDIN)) {
    $inputs[] = trim($line);
};
$k = (int)$inputs[0];
list($a, $b) = explode(" ", $inputs[1]);
$a = (int) $a;
$b = (int) $b;

for ($i = $a; $i <= $b; $i++) {
    if ($i % $k == 0) {
        echo "OK\n";
        exit;
    }
}
echo "NG\n";