#include <bits/stdc++.h>

int ri() {
	int n;
	scanf("%d", &n);
	return n;
}

int main() {
	int p = ri(), q = ri();
	long double l = 1, r = 1000000000000000000;
	for (int i = 0; i < 200; i++) {
		long double n = l + (r - l) / 2;
		if (p + q * n * std::log2(n) <= n * n) r = n;
		else l = n;
	}
	printf("%.11Lf\n", l);
	return 0;
}