#include <iostream>
#include <string>
#include <fstream>
#include <iomanip>
#include <vector>
using namespace std;
static const int MAX_N = 1000005;

int main()
{
	int n, dp[MAX_N];
	cin >> n;
	dp[1] = 1;
	dp[2] = 2;
	dp[3] = 2;
	for (int i = 4; i <= n; i++)
	{
		dp[i] = dp[i - 2] + dp[i - 3];
		dp[i] %= 1000000007;
	}
	cout << dp[n] << endl;
	return 0;
}