#include <bits/stdc++.h>
using namespace std;

using ll = long long;
#define rep(i, n) for(int i = 0; i < n; i++)

int main() {
	int N;
	double r;
	cin >> N >> r;
	double x = 100, ans = 0;
	rep(i, N) {
		if( i + 1 < N) {
			ans += x;
			x = (1 - r) * x;
		}
		else ans += x;
	}
	cout << fixed << setprecision(12) << ans << endl;
}