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)

//AUTHOR: RAVAN_2070
//PUNE INSTITUTE OF COMPUTER TECHNOLOGY
/*
    I LOVE CLARICE STARLING

     ♥LOVE♥        ♥LOVE♥
  ♥LOVE♥♥LOVE♥  ♥LOVE♥♥LOVE♥
♥LOVE♥♥LOVE♥♥LOVE♥♥LOVE♥♥LOVE♥
   ♥LOVE♥♥LOVE♥♥LOVE♥♥LOVE♥
      ♥LOVE♥♥LOVE♥♥LOVE♥
         ♥LOVE♥♥LOVE♥
            ♥LOVE♥
               ♥


    EXPLAINATION BELOW->
   
*/
#include<bits/stdc++.h>
using namespace std;
typedef unsigned long long int ull;
typedef long long int ll;
typedef long double ld;
typedef vector<ll> vi;
typedef vector<pair<ll,ll>> vii;
typedef pair<ll,ll> pii;
typedef map<ll,ll> mii;
#define MOD7 1000000007
#define MOD9 1000000009
#define pi 3.1415926535
#define Test_cases ll TC;cin>>TC;while(TC--)
#define fastio ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define pb push_back
#define mp make_pair
#define F first
#define S second
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(), x.rend()
#define sp(x) fixed<<setprecision(x)
#define sz(x) (ll)(x.size())
#define fo(i,a,b) for(i=a;i<b;i++)
#define foe(i,a,b) for(i=a;i<=b;i++)
void solve()
{
    int k,a,b,i;cin>>k>>a>>b;
    foe(i,a,b)
    {
        if(i%k==0){cout<<"OK\n";return;}
    }
    cout<<"NG\n";
}
int main()
{
   fastio
   solve();
  return 0;
}
//map<ll,ll,greater<int>> to sort in descending order ,in iterator declaration no greater<int>
//if you want to apply lowerbound on set use s.lower_bound(key),not the one used for vector
/* TIPS FOR DEBUGGING
 * Check if values are not overflowing (use long long where required)
 * Check if ranges are inclusive or not.
 * Check properly if greedy will work or not before using it.
 * Check EDGE CASES!! Seriously, even in 2B, saving 8 points by being
 * 2 minutes faster will bite you in the ass if you don't make sure
 * it works on edge cases.
 * Keep adding to this list.
*/