#include<bits/stdc++.h>
#define REP(i,n) for(int i=0;i<n;i++)
#define LOOP(i,x,n) for(int i=x;i<n;i++)
#define ALL(v) (v).begin(),(v).end()
#define PB push_back
#define MP make_pair
#define FR first
#define SC second
#define int long long
using namespace std;
const int MOD=1000000007;
const int INF=9000000009;

int dp[10000006];

signed main(){
  int n;
  cin>>n;
  dp[0]=1;dp[1]=2;dp[2]=2;
  LOOP(i,3,n+1)dp[i]=(dp[i-2]+dp[i-3])%MOD;
  cout<<dp[n-1]<<endl;
  return 0;
}