#include <iostream>
#include <algorithm>

using namespace std;

const long long int MOD = 1e9 + 7;

int main()
{
    long int N = 0;
    long int dp[1000010];

    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];
    }

    cout << dp[N - 1] % MOD << endl;
    return 0;
}