HDU ACM 11 2047 阿牛的EOF牛肉串

#include <iostream>
using namespace std;
int main()
{
int n;
__int64 Lu[41];
while (cin >> n)
{
Lu[0] = 3;
Lu[1] = 8;
int s = 2, t = 1;
for (int i = 2; i < n; i++)
Lu[i] = 2 * (Lu[i - 1] + Lu[i - 2]);
cout << Lu[n - 1] << endl;
}
return 0;
}