//Author - Rahil Malhotra
#include "bits/stdc++.h"
using namespace std;
 
template <typename T> void print(T t) { cout<<t<<endl; }
template<typename T, typename... Args> void print(T t, Args... args) { cout<<t<<" "; print(args...); }
 
#define IOS ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define endl '\n'
#define int long long
#define double long double

int mod = 998244353;
int arr[200005]={};
int inv(int x)
{
    int r,y;
    for(r=1,y=mod-2;y>0;x=(x*x)%mod,y/=2)
        if(y%2==1)
            r=r*x%mod;
    return r;
}
int power(int x,int y,int p)
{ 
    int res = 1;      
    x = x % p;  
    while (y > 0) 
    { 
        if((y & 1)==1) 
            res = (res * x) % p; 
        y = y >> 1;  
        x = (x * x) % p;  
    } 
    return res; 
} 
int32_t main() 
{
    IOS;
    int n;
    cin>>n;
    arr[0]=1;
    arr[1]=1;
    for(int i=2;i<=n+2;i++)
        arr[i]=(arr[i-1]+arr[i-2])%mod;
    cout<<(arr[n-1]*inv(power(2,n,mod)))%mod;
} 