#include<bits/stdc++.h>
using namespace std;
int main()
{
	int k,i=1,n=1;
	double s=0,j;
	cin>>k;
	while(s<k)
	{
		n++;
		j=1/i;
		s=s+j;
		i++;
	}
	cout<<n;
	return 0;
}