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<bits/stdc++.h>
#define ll     long long int
#define pb     push_back
#define fast               ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define pb                push_back
#define all(v)             v.begin(),v.end()
#define inp(V,n)      for(int i=0;i<n;i++){cin >> V[i];}
#define oup(V,n)     {for(int i=0;i<n;i++){cout <<  V[i] << " "  ;} cout << endl;}
using namespace std ;
int main()
{
     fast;
     int t=1;
    // cin>>t;
     while(t--)
     {
       ll n,i,j=1,k,l,m,ans=0,sum=0,result,a,b,c,d;
       cin>>k>>a>>b;
      n=a-b;
        if(k==1)
            cout<<"OK"<<endl;
        else
        {
            if(n>=k)
                cout<<"OK"<<endl;
            else
                cout<<"NG"<<endl;
        }



     }

     return 0;
}