#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);
}
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