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 Julia (1.4.0) (judge verdict: Accepted)

const double = Float64
const int = Int64
const vint = Vector{int}
const vdouble = Vector{double}

int(x) = parse(int,x)
parseint(x) = parse(int, x)

function readint()
  moji = readline(stdin)
  moji = split(moji)
  return map(parseint,moji)

end

function main()
  k = readint()[1]
  a,b = readint()
  if a%k==0 || b÷k - a÷k >= 1 
    println("OK")
  else
    println("NG")
  end
end

main()