#include <iostream>
using namespace std;

#define N_MAX 1000000
#define A 1000000007

int n;
unsigned long long dp[N_MAX + 1] ={0};
int ans = 0;

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