10223

#include <iostream>
#include <cstdio>

#define ll long long

using namespace std;

ll catalan[25];

ll findcatalan(int n)
{
	ll res = 1;
	int lim;
	for(int i=n+2;i<=2*n;i++)
	{
		if(i%2==0)
		res*=2;
		else
		res*=i;
	}
	if((n+2)%2==0)
	lim = (n+2)/2;
	else
	lim = (n+3)/2;
	for(int i=2;i<lim;i++)
	{
		res/=i;
	}
	return res;
}

int binSearch(ll num)
{
    int lw=0,hi=17;
    int mid;
    /*while(lw<hi)
    {
        mid=lw+(hi-lw)/2;
        if(catalan[mid]<num)
        lw = mid+1;
        else if(catalan[mid]==num)
        return mid;
        else if(catalan[mid]>num)
        hi = mid;
    }*/
    for(int i=1;i<20;i++)
    {
            if(num==catalan[i])
            return i;
    }
    return 0;
}
int main()
{
	catalan[0]=1;
	catalan[1]=1;
	catalan[2]=2;
	ll num;
	int idx;
	for(int i=3;i<20;i++)
	{
		catalan[i] = findcatalan(i);
	}
	while(cin>>num)
	{
		idx = binSearch(num);
		cout<<idx<<"\n";
	}
	return 0;
}