#include<bits/stdc++.h>
#define ll long long

using namespace std;
const int N=1e6;
int n;
ll a[N+10],s[N+10];
int main(){
	//freopen(".in","r",stdin);
	//freopen(".out","w",stdout);
	ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
	int o=0;
	while(cin>>n){
		if((++o)>=40){
//			break;
		}
		int pos;
		for(int i=1;i<=n;++i){
			cin>>a[i];
			s[i]=s[i-1]+a[i]+1;
			if(a[i]>=s[i-1]){
				pos=i;
			}
		}
		int cnt=0;
		ll sum=0;
		for(int i=pos+1;i<=n;++i){
			cnt+=(a[i]<=cnt);
			sum+=max(0ll,a[i]-cnt);
		}
		if(sum+s[pos-1]<a[pos]){
			cout<<"Bad Rescue\n";
		}
		else if(sum+s[pos-1]==a[pos]){
			cout<<pos<<'\n';
		}
		else{
			cout<<"Unknown\n";
		}
	}
	return 0;
}