#include<bits/stdc++.h>
using namespace std;
struct node
{
	int data;
	node *next;
};
int n;
node *head,*p,*r;
int main()
{
	cin>>n;
	n*=2;
	bool flag=1;
	head=new node;
	head->data=1;
	head->next=NULL;
	r=head;
	for(int i=2;i<=n;i++)
	{
		p=new node;
		p->data=i;
		p->next=NULL;
		r->next=p;
		r=p; 
	}
	p->next=head;
	r=head;
	int m=n/2; 
	while(flag)
	{
		m++;
		for(int i=1;i<=n/2;i++)
		{
			for(int j=1;j<=m-2;j++)
			{
				r=r->next;
			}
			if(r->next->data<=n/2) break;
			else 
			{
				r->next=r->next->next;
				r=r->next;
			} 
			if(i==n/2) flag=0;
			
		 } 
	}
	cout<<m<<endl;
	
	return 0;
}