#include <bits/stdc++.h>
#include <random>
#include <chrono>
using namespace std;
//#pragma GCC optimize("Ofast")
//#pragma GCC optimize ("unroll-loops")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<ll,ll> pll;
//mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
const int MOD1=1e9+7;
const int MOD2=998244353;
const ll INF=2*1e18;
const ld PI=3.14159265358979323846;
ll gcd(ll a,ll b){if(b==0) return a; return gcd(b,a%b);}
ll fpow(ll a,ll b,ll m)
{
    if(!b) return 1;
    ll ans=fpow(a*a%m,b/2,m);
    return (b%2?ans*a%m:ans);
}
ll inv(ll a,ll m) {return fpow(a,m-2,m);}
#define MottoHayaku ios::sync_with_stdio(false);cin.tie(0);
#define rep(i,n) for(ll i=0;i<n;i++)
#define rep1(i,n) for(ll i=1;i<=n;i++)
#define repk(i,m,n) for(int i=m;i<n;i++)
#define F first
#define S second
#define pb push_back
//#define mp make_pair
#define SZ(a) ((ll)a.size())
#define reset(a) memset(a,0,SZ(a))
#define cd(a,b) ((a+b-1)/b)
#define pow2(a) (1LL<<a)
#define LB(a,x) (lower_bound(a.begin(),a.end(),x))
#define LPOS(a,x) (lower_bound(a.begin(),a.end(),x)-a.begin())
#define UB(a,x) (upper_bound(a.begin(),a.end(),x))
#define UPOS(a,x) (upper_bound(a.begin(),a.end(),x)-a.begin())
#define uni(c) c.resize(distance(c.begin(),unique(c.begin(),c.end())))
#define unisort(c) sort(c.begin(),c.end()),uni(c)
ll f[200005];
int main()
{
    MottoHayaku
    ll n;
    cin>>n;
    f[1]=f[2]=1;
    for(int i=3;i<=n;i++) f[i]=(f[i-1]+f[i-2])%MOD2;
    cout<<f[n]*inv(fpow(2,n,MOD2),MOD2)%MOD2;
}
