n=int(input())
a=list(map(int,input().split()))
b=sorted(a)
c=[]
for i in range(n-1,-1,-1):
    c.append(b[i])
if (a==b or  c==a):
    print("Good")
else:
    print("No")
/**************************************************************
	Problem: 1807
	User: admin
	Language: Python
	Result: Accepted
	Time:195 ms
	Memory:34480 kb
****************************************************************/