#include "bits/stdc++.h"
using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> veci;
typedef vector<string> vecs;
//template<class T,class U> using Hash=unordered_map<T,U>;

#define REP(i, a, n) for(ll i = a; i < (ll)n; i++)
#define RREP(i, a, n) for(ll i = n-1; i >= a; i--)
#define rep(i, n) REP(i, 0, n)
#define rrep(i, n) RREP(i, 0, n)
#define MD 1000000007

template<class T> T read(){T a;cin >> a;return a;}
template<class T> void read(T& a){cin >> a;}
template<class T> void rarr(T a, int n){for(int i = 0; i < n; i++) {cin >> a[i];}}
template<class T> void write(T a){cout << a << endl;}
template<class T> void writes(vector<T> a, const char* c = " "){cout << a[0];for(int i = 1; i < (int)a.size(); i++)cout << c << a[i];cout << endl;;}
void write(double a){cout << fixed << setprecision(12) << a << endl;}
void write(long double a){cout << fixed << setprecision(12) << a << endl;}
template<class T> void warr(T a, int n, const char* c = " "){cout << a[0];for(int i = 1; i < n; i++)cout << c << a[i];cout << endl;}
void split(string s, string delim, veci& result){result.clear();string::size_type pos = 0;while(pos != string::npos){string::size_type p = s.find(delim, pos);if(p == string::npos){result.push_back(atoi(s.substr(pos).data()));break;}else {result.push_back(atoi(s.substr(pos, p - pos).data()));}pos = p + delim.size();}}
void split(string s, string delim, vecs& result){result.clear();string::size_type pos = 0;while(pos != string::npos){string::size_type p = s.find(delim, pos);if(p == string::npos){result.push_back(s.substr(pos));break;}else {result.push_back(s.substr(pos, p - pos));}pos = p + delim.size();}}
ll gcd(ll a, ll b){while(true){ll k = a % b;if(k == 0)return b;a = b;b = k;}}
ll comb(ll n, ll m){ll p=1;m=min(m,n-m);for(ll i=1;i<=m;i++){p*=n-i+1;p/=i;}return p;}

typedef unsigned long long Num;

struct Matrix {
	vector<vector<Num> > v, w;
    static Num MOD;
	Matrix() {}
	Matrix(int n, int m): v(n, vector<Num>(m)) { assert(n > 0 && m > 0); }
	inline int height() const { return (int)v.size(); }
	inline int width() const { return (int)v[0].size(); }
	inline Num& at(int i, int j) { assert(0 <= i && i < height() && 0 <= j && j < width()); return v[i][j]; }
	inline const Num& at(int i, int j) const { assert(0 <= i && i < height() && 0 <= j && j < width()); return v[i][j]; }
	static Matrix identity(int n) {
		Matrix A(n, n);
		rep(i, n) A.at(i, i) = 1;
		return A;
	}
	inline static Matrix identity(const Matrix& A) {
		assert(A.height() == A.width()); return identity(A.height()); }
	Matrix& operator*=(const Matrix& B) {
		int n = height(), m = B.width(), p = B.height();
		assert(p == width());
		w.resize(n, vector<Num>(m, 0));
		rep(i, n) rep(j, m) {
			//MOD = 1000000007の場合、1000000012000000036となり、
			//2^64にオーバーフローするのは2^64-1-1000000006^2くらいで、それは最上位4bitが立っているから
			//！MODが違う場合、書き換えること！
			Num x = 0;
			rep(k, p) {
				x += at(i, k) * B.at(k, j);
				//if((x >> 60) == 0xf)
                x %= MOD;
			}
			x %= MOD;
			w[i][j] = x;
		}
		v.swap(w);
		return *this;
	}
	Matrix& operator+=(const Matrix& B) {
		int n = height(), m = width();
		assert(n == B.height() && m == B.width());
		rep(i, n) rep(j, m) {
			at(i, j) += B.at(i, j);
			if(at(i, j) >= MOD) at(i, j) -= MOD;
		}
		return *this;
	}
	void undomult() { v.swap(w); }
};

Num Matrix::MOD=1000000007ULL;

ostream& operator<<(ostream& o, const Matrix& A) {
	int n = A.height(), m = A.width();
	rep(i, n) {
		o << "["; rep(j, m) o << A.at(i, j) << (j+1 == m ? "]\n" : ",");
	}
	return o;
}

/* ジェネリックなべき乗算 */
template<typename Mat>
Mat operator^(const Mat& t, ll k) {
	Mat A = t, B = Mat::identity(t);
	while(k) {
		if(k & 1) {
			B *= A;
		}
		A *= A;
		k >>= 1;
	}
	return B;
}


int main(void)
{
    int n;
    Matrix mat(2,2);
    mat.at(0,0)=1;mat.at(0,1)=3;
    mat.at(1,0)=1;mat.at(1,1)=1;
    cin>>n;
    if(n==0)write(1),exit(0);
    Matrix::MOD=1e3;
    mat=mat^n;
    write((mat.at(0,0)*2+1000-((n+1)%2))%1000);
    return 0;
}