#include<bits/stdc++.h>
using namespace std;
double n,ans,i=1.0;
int main(){
   cin>>n;
   while(ans<n){
   	ans+=1/i;
	   i++;
   }
   	if(ans>=n)cout<<i-1;
   return 0;
}

/**************************************************************
	Problem: 1078
	User: chenjingqi
	Language: C++
	Result: Accepted
	Time:8 ms
	Memory:2072 kb
****************************************************************/