#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using ll = long long;
#define rep(i,n) for(int i=0;i<(int)(n);i++)
using mint = atcoder::modint1000000007;

int main(){
	int n;
	cin>>n;
	double r;
	cin>>r;
	vector<double> v(n);
	v.at(0)=100;
	rep(i,n-1) v.at(i+1)=v.at(i)*(1-r);
	double sm=0;
	rep(i,n) sm+=v.at(i);
	cout<<fixed<<setprecision(10);
	cout<<sm<<endl;
}