#include <bits/stdc++.h>
using namespace std;
int main(){
    int n,a[110],i;
    cin>>n;
    for(i = 1;i <= n;i++){
        cin>>a[i];
    }
     
    int f1 = 1;//假设递增
    int f2 = 1;//假设递减 
     
    for(i = 1;i < n;i++){
        if(a[i] > a[i+1]){
            f1 = 0;
        }
         
        if(a[i] < a[i+1]){
            f2 = 0;
        }
    }
     
    if(f1 == 0 && f2 == 0){
        cout<<"No";
    }else{
        cout<<"Good";
    }
    return 0;
}
/**************************************************************
	Problem: 1807
	User: wangyiyang
	Language: C++
	Result: Accepted
	Time:16 ms
	Memory:2072 kb
****************************************************************/