#include<iostream>
#include<vector>
#include<iomanip>
using namespace std;

int main(){
	double n,r;
	cin >> n >> r;
	vector<double> v(n + 1);
	v[1] = 100;
	double ans = 0;
	for(int i = 1;i <= n;i++){
		if(i < n) v[i + 1] = (1 - r) * v[i];
		ans += v[i];
	}
	
	cout << fixed << setprecision(20) << ans << endl;
}