// yuki 1042 愚直大学
// 2021.8.12

#include <stdio.h>
#include <math.h>

int P, Q;
int calc(double N) {
	double y = 1.0/Q*(N-P/N) - log10(N)/log10(2.0);
	return y >= 0;
}

int main()
{
	scanf("%d%d", &P, &Q);
	double l = 1, r = 1e13;
	int n = 150; while (n--) {
		double m = (l+r)/2;
		if (calc(m)) r = m; else l = m;
	}
	printf("%.9lf\n", l);
	return 0;
}