#include<iostream>
#include<vector>
#include<algorithm>

using namespace std;
#define int long long
int MOD = 1e9+7;

signed main(){
    int N; cin>>N;

    vector<int> dp(N+1);
    dp = {0,1,2,2};
    for(int i=4;i<=N;i++){
        dp[i] = (dp[i-2] + dp[i-3]) % MOD;
    } 

    cout<<dp[N]<<endl;
}