HDU ACM 11 2064 汉诺塔III

题目很简单。但是有坑

#include <iostream>
using namespace std;
int main()
{
	__int64 n, Lu[35];
	while (cin >> n)
	{
		Lu[1] = 2;
		for (int i = 2; i <= n; i++)
			Lu[i] = 3 * Lu[i - 1] + 2;
		cout << Lu[n] << endl;
	}
	return 0;
}