//
// Darsein AC : O(5^4)
// implement : 5 min
// debug     : 0 min
//

#include<iostream>
using namespace std;

bool rec(int la, int ra, int lb, int rb){
  if(la>=5 && ra>=5)return 0;
  if(lb>=5 && rb>=5)return 1;

  bool f = true;
  if(la<5 && lb<5)f &= rec(lb+la,rb,la,ra);
  if(la<5 && rb<5)f &= rec(lb,rb+la,la,ra);
  if(ra<5 && lb<5)f &= rec(lb+ra,rb,la,ra);
  if(ra<5 && rb<5)f &= rec(lb,rb+ra,la,ra);

  return !f;
}

int main(){
  int la, ra, lb, rb;
  cin >> la >> ra >> lb >> rb;
  
  cout << (rec(la,ra,lb,rb)?"ISONO":"NAKAJIMA") << endl;
}