#include<bits/stdc++.h>
using namespace std;
int main()
{
    double p;
    cin >> p;
    double left = 1.00-p;
    int cnt = 0;
    double sum = 0;
    while(sum+left<=1)
    {
        sum+=left;
        cnt++;
    }
    cout<<cnt-1<<endl;
}