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 C++ (GCC 9.2.1) (judge verdict: Accepted)

#include <bits/stdc++.h>
using namespace std;

int main() {
 
  int a,b,c;
  //string s;
  
  cin >> a ;
  cin >> b >> c ;
  
  int count = b;
  int judge = 0;
 
  for(int i = b; i<=c ; i++){
  	if(count%a==0){
    	judge = 1;
    }
    count++;
  }
  
  if(judge == 0){
  	cout << "NG" << endl;
  }else{
  	cout << "OK" << endl;
  }
  return 0;
  
}