#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n=0,x;
    float s;
    cin>>x;
    while(s<=x){
        n++;
        s+=1.00*1/n;
    }
    cout<<n;
    return 0;
}
/**************************************************************
	Problem: 1078
	User: fuyijun
	Language: C++
	Result: Accepted
	Time:7 ms
	Memory:2072 kb
****************************************************************/