A. Filling Shapes1000 / 找规律

Posted 2021-10-16 幽殇默

https://codeforces.com/problemset/problem/1182/A

#include<bits/stdc++.h>
using namespace std;
int main(void)
{
	int n; cin>>n;
	if(n&1) puts("0");
	else 
	{
		int k=n/2;
		long long int ans=1; 
		for(int i=1;i<=k;i++) ans*=2;
		cout<<ans; 
	}
	return 0;
}