#include <bits/stdc++.h>
using namespace std;
#define rep(i, a) for (int i = 0; i < (a); i++)
#define rep2(i, a, b) for (int i = (a); i < (b); i++)
#define repr(i, a) for (int i = (a) - 1; i >= 0; i--)
#define repr2(i, a, b) for (int i = (b) - 1; i >= (a); i--)
template<class T1, class T2> bool chmin(T1 &a, T2 b) { return b < a && (a = b, true); }
template<class T1, class T2> bool chmax(T1 &a, T2 b) { return a < b && (a = b, true); }
typedef long long ll;

const ll mod = 1000;

struct matrix {
	vector<vector<ll>> dat;
	int n;
	matrix(int n) : n(n), dat(n, vector<ll>(n)) {}
	static matrix I(int n) {
		matrix ret(n);
		rep(i, n) ret[i][i] = 1;
		return ret;
	}
	matrix pow(ll b) {
		matrix ret = I(n);
		for (matrix A = *this; b > 0; A = A * A, b /= 2) if (b & 1) ret = ret * A;
		return ret;
	}
	matrix operator*(matrix &b) {
		matrix ret(n);
		rep(i, n) rep(j, n) rep(k, n) (ret[i][j] += dat[i][k] * b[k][j]) %= mod;
		return ret;
	}
	vector<ll> &operator[](int i) { return dat[i]; }
};

int main() {
	vector<int> a(100);
	matrix A(2);
	A.dat = {
		{ 0, 1 },
		{ 2, 2 },
	};
	ll n;
	cin >> n;
	A = A.pow(n);
	ll ans = (A[0][0] + A[0][1]) * 2 % mod;
	if (n % 2 == 0) (ans += mod - 1) %= mod;
	cout << ans << endl;
	return 0;
}