#include <iostream>  
using namespace std;  
int main(){  
    int i = 1,n,x;
    double s = 0;
    cin>>x;
     while(s <= x){ 
   s = s + 1.0 / i;
   i++;
}
cout<<i - 1<<endl;
    return 0;  
  } 

/**************************************************************
	Problem: 1078
	User: admin
	Language: C++
	Result: Accepted
	Time:9 ms
	Memory:2072 kb
****************************************************************/