import java.util.*;
import java.lang.*;
import java.io.*;
import java.math.*;
class Ideone
{
public static void main (String[] args) throws java.lang.Exception
{
Scanner in = new Scanner(System.in);
double k = in.nextDouble();
double p = in.nextDouble();
double s = in.nextDouble();
double years = 0;
if(s > k)
years = Math.ceil(Math.log(s/k)/Math.log(1+(p/100)));
System.out.println(years);
}
}