#include<bits/stdc++.h>
using namespace std;
int main()
{
float x,n=0,s=0;
cin>>x;
while(s<=x){
n+=1;
s+=1.0/n;
}
cout<<n;
return 0;
}
/**************************************************************
Problem: 1078
User: ccf
Language: C++
Result: Accepted
Time:14 ms
Memory:2072 kb
****************************************************************/