#include "bits/stdc++.h"
using namespace std;
#define FOR(i,j,k) for(int (i)=(j);(i)<(int)(k);++(i))
#define rep(i,j) FOR(i,0,j)
#define each(x,y) for(auto &(x):(y))
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define debug(x) cout<<#x<<": "<<(x)<<endl
#define smax(x,y) (x)=max((x),(y))
#define smin(x,y) (x)=min((x),(y))
#define MEM(x,y) memset((x),(y),sizeof (x))
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<ll> vll;

const int M = 1000;
int n, t[M + 1][M + 1], sk = 0;

int main(){
    cin >> n;
    ll x=2, y=2, z=2;
    for(int i = 2; i <= n;){
        x = 2 * (y + z) % M;
        int ad = 0;
        if(t[y][z]&&!sk){
            int cyc = i - t[y][z];
            int rem = n - i;
            ad = rem / cyc*cyc;
        }
        if(ad>0){
            i += ad;
            sk = 1;
        }else{
            t[y][z] = i;
            i++;
            z = y;
            y = x;
        }
    }
    if(n % 2 == 0)
        if(--x < 0)x += M;
    cout << x << endl;
}