#include<iostream>
using namespace std;

int INF = 1e9 + 7;

int main() {
	int n;
	cin >> n;
	int dp[1000010][3];
	for (int i = 0;i < 3;i++)dp[0][i] = 0;
	dp[1][0] = 0;
	dp[1][1] = 1;
	dp[1][2] = 0;
	for (int i = 2;i <= n;i++) {
		dp[i][0] = (dp[i - 1][1] + dp[i - 1][2]) % INF;
		dp[i][1] = dp[i - 1][0] % INF;
		dp[i][2] = dp[i - 1][1] % INF;
	}
	cout << (dp[n][0] + dp[n][1] + dp[n][2]) % INF << endl;
}