#include <iostream>
#include <cstdio>
#include <cmath>
#include <vector>
#include <queue>

#include <map>
#include <set>
#include <string>
#include <algorithm>
#include <functional>
using namespace std;
#define FOR(i,a,b) for (int i=(a);i<(b);i++)
#define RFOR(i,a,b) for (int i=(b)-1;i>=(a);i--)
#define REP(i,n) for (int i=0;i<(n);i++)
#define RREP(i,n) for (int i=(n)-1;i>=0;i--)
#define INF 1<<30
#define ALEN(ARR) (sizeof(ARR) / sizeof((ARR)[0]))
#define MP make_pair
#define mp make_pair
#define pb push_back
#define PB push_back
#define DEBUG(x) cout<<#x<<": "<<x<<endl
#define ll long long
#define ull unsigned long long
#define MOD 1000000007

ll dp[1000001];

int main(){
	cin.tie(0);
	ios::sync_with_stdio(false);
	cout.precision(16);
	
	int n;
	cin >> n;
	
	dp[0]= 1;
	dp[1] = 2;
	dp[2] = 2;
	for(int i = 3; i < n; i++) {
		dp[i] = (dp[i-2] + dp[i-3]) % MOD;
	}
	
	cout << dp[n-1] << endl;
}