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

typedef long long ll;
#define bug(a) cout<<#a<<" : "<<a<<endl;
#define bug2(a,b) cout<<#a<<" : "<<a<<"\t"<<#b<<" : "<<b<<endl;
#define yes cout<<"Yes\n";
#define no cout<<"No\n";

signed main(){
    ios::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    int t=1;
    // cin>>t;
    int cs=1;
    while(t--){
        // cout<<"Case "<<cs++<<": \n";
        int n;cin>>n;
        while(1){
            if(n%2==0)break;
            n--;
        }
        cout<<n<<endl;
        
    }
    return 0;
}