package Practice;

import java.io.BufferedReader;

import java.io.InputStreamReader;

import java.util.Stack;

import java.util.StringTokenizer;

public class B12789 { //µµÅ°µµÅ° °£½Äµå¸®¹Ì

static int order = 1;

static Stack<Integer> S = new Stack<>();

public static void main(String[] args) throws Exception {

// TODO Auto-generated method stub

BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

int N = Integer.parseInt(br.readLine());

int[] num = new int[N];

StringTokenizer st = new StringTokenizer(br.readLine());

for(int i = 0; i < N; i++) num[i] = Integer.parseInt(st.nextToken());

for(int i = 0; i < N; i++) {

if(num[i] == order) {

order++;

continue;

}

check_stack();

S.push(num[i]);

}

check_stack();

if(S.isEmpty()) System.out.println("Nice");

else System.out.println("Sad");

}

static void check_stack() {

while(!S.isEmpty()) {

int cur = S.peek();

if(cur != order) break;

order++;

S.pop();

}

}

}