#include <iostream>
#include <string>
#include <vector>
#include <set>
#include <cmath>
#include <algorithm>
#include <iomanip>
#include <queue>
using ll = long long;
using namespace std;

ll MOD = 1e9 + 7;
ll dp[1000010];
int main(void)
{
    int N;
    cin >> N;
    dp[1] = 1;
    dp[2] = 2;
    dp[3] = 2;
    dp[4] = 3;
    for (int i = 5; i <= N; ++i)
    {
        dp[i] = (dp[i - 2] + dp[i - 3]) % MOD;
    }
    cout << dp[N] << endl;
    return 0;
}