#include<bits/stdc++.h>
#define Add(x,y) (x+y>=mod)?(x+y-mod):(x+y)
#define lowbit(x) x&(-x)
#define pi pair<ll,ll>
#define pii pair<ll,pair<ll,ll>>
#define iip pair<pair<ll,ll>,ll>
#define ppii pair<pair<ll,ll>,pair<ll,ll>>
#define fi first
#define se second
#define full(l,r,x) for(auto it=l;it!=r;it++) (*it)=x
#define Full(a) memset(a,0,sizeof(a))
#define open(s1,s2) freopen(s1,"r",stdin),freopen(s2,"w",stdout);
using namespace std;
typedef double db;
typedef unsigned long long ull;
typedef long long ll;
bool Begin;
const ll M=2,mod=1000;
inline ll read(){
    ll x=0,f=1;
    char c=getchar();
    while(c<'0'||c>'9'){
        if(c=='-')
          f=-1;
        c=getchar();
    }
    while(c>='0'&&c<='9'){
        x=(x<<1)+(x<<3)+(c^48);
        c=getchar();
    }
    return x*f;
}
inline void write(ll x){
	if(x<0){
		putchar('-');
		x=-x;
	}
	if(x>9)
	  write(x/10);
	putchar(x%10+'0');
}
ll n,ans; 
struct Mat{
	ll a[M][M];
	Mat(){memset(a,0,sizeof(a));}
	ll* operator[](ll i){
		return a[i];
	}
	void init(){
		for(int i=0;i<M;i++)
		  a[i][i]=1;
	}
	friend Mat operator*(Mat a,Mat b){
	    Mat c;
	    for(int i=0;i<M;i++)
	      for(int j=0;j<M;j++)
		    for(int k=0;k<M;k++)
		      c[i][j]=(c[i][j]+(a[i][k]*b[k][j])%mod)%mod;
	    return c;
	}
}t,base;
Mat qpow(Mat a,ll b){
	Mat ans=t;
	while(b){
		if(b&1ll)
		  ans=ans*a;
		a=(a*a);
		b>>=1ll;
	}
	return ans;
}
bool End;
int main(){
//	open("mul.in","mul.out");
	n=read()+1;
	if(n==1){
		puts("1");
		exit(0);
	}
	t[0][0]=2,t[0][1]=2;
	base[0][0]=2,base[0][1]=1,base[1][0]=2;
	t=qpow(base,n-2);
	ans=t[0][0];
	if(n&1ll)
	  ans=(ans+mod-1)%mod;
	write(ans);
	return 0;
}