노트

n = int(input()) line = list(map(int,input().split())) passed = [] stack = [] number = 1 while line: temp = line.pop(0) if temp==number: passed.append(temp) number+=1 else: stack.insert(0,temp) while stack: num = stack.pop(0) if len(stack)+1>=0 and num==number: passed.append(num) number+=1 else: stack.insert(0,num) break if not stack: print("Nice") else: print("Sad")