#include<iostream>

using namespace std;

int dfs(int ar, int al, int br, int bl, int turn) {
	int na,nb,nc,nd;
	if (ar > 4 && al > 4) return -1;
	if (br > 4 && bl > 4)return 1;

	if (turn == 1) {
		if (br < 5) {
			if (ar < 5) {
				na = dfs(ar, al, br + ar, bl, -1);
			}else{
				na = -1;
			}
			if (al < 5) {
				nb = dfs(ar, al, br + al, bl, -1);
			}else{
				nb = -1;
			}
		}
		else {
			na = nb = -1;
		}
		if (bl < 5) {
			if (ar < 5) {
				nc = dfs(ar, al, br, bl + ar, -1);
			}else{
				nc = -1;
			}
			if (al < 5) {
				nd = dfs(ar, al, br, bl + al, -1);
			}else{
				nd = -1;
			}
		}else{
			nc = nd = -1;
		}
		if (na == -1&&nb == -1&&nc == -1&&nd == -1) {
			return -1;
		}
		else {
			return 1;
		}
	}
	if (turn == -1) {
		if (ar < 5) {
			if (br < 5) {
				na = dfs(ar + br, al, br, bl, 1);
			}else{
				na = 1;
			}
			if (bl < 5) {
				nb = dfs(ar + bl, al, br, bl, 1);
			}else{
				nb = 1;
			}
		}
		else {
			na = nb = 1;
		}
		if (al < 5) {
			if (br < 5) {
				nc = dfs(ar, al + br, br, bl, 1);
			}else{
				nc = 1;
			}
			if (bl < 5) {
				nd = dfs(ar, al + bl, br, bl, 1);
			}else{
				nd = 1;
			}
		}
		else {
			nc = nd = 1;
		}
		if (na == 1&&nb == 1&&nc == 1&&nd == 1) {
			return 1;
		}
		else {
			return -1;
		}
	}
}
//1...ISONO
//-1...NAKAJIMA

int main(void) {
	int ar, al, br, bl, ans;
	cin >> ar >> al >> br >> bl;
	ans = dfs(ar, al, br, bl, 1);

	if(ans==1)cout << "ISONO" << endl;
	else cout << "NAKAJIMA" << endl;
}