#include <iostream>
#define rep(i, l, n) for (int i = (l); i < (n); i++)
using namespace std;


int main(void) {
	int n;	 cin >> n;
	double p; cin >> p;

	if (n >= 200) {
		cout << 1 << endl;
		return 0;
	}

	double ans = 0.0;
	double t = 1.0;
	rep(i, 0, n) {
		ans += t * p;
		t *= 1 - p;
	}

	cout << ans << endl;
	return 0;
}