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: Wrong Answer)

#include<iostream>
#include<bits/stdc++.h>
#include<algorithm>
#include<string.h>
#include<math.h>
#include <cstdlib>
#include <stdlib.h>
#define FasterIO     ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define PI acos(-1)
#define all(a) a.begin(),a.end()
#define f first
#define s second
#define pb push_back
#define ppb pop_back
#define pf push_front
#define ppf pop_front
#define mp make_pair
#define f0(i,n) for(i=0;i<n;i++)
#define f1(i,n) for(i=1;i<n;i++)
#define f1n(i,n) for(i=1;i<=n;i++)
#define szf sizeof()
#define sz size()
#define ln length()
#define MOD 1000000007
using namespace std;
using ll=long long;
int cnt,element;
int main()
{
    int a,b,n,rafi;
    cin>>n;
    cin>>a>>b;
    rafi=b-a;
    if(rafi>=n || a%n==0 || b%n==0)
    {
        cout<<"OK"<<endl;
    }
    else{
        cout<<"NG"<<endl;
    }
    return 0;
}