#include <iostream>
#include <cmath>
long M(double x, double p_min, long n)
{
    n--;
    double p = 1;
    double b = std::pow(x, n + 1);
    long m = n;
 
    while (p > 1 - p_min)
    {
        p = p - b;
        m++;
        b = b * (1 - x) * ((double)m / (m - n));
    }
 
    return m;
}

int main() {
	std::cout << M(0.25, 0.3, 2);
}