#include <stdio.h>
#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;
using namespace std;
#define rep(i,n) for(int i=0;i<(n);i++)
#define Inf 1000000001


int main(){
	
	int n;
	cin>>n;
	
	double ans = 0.0;
	double p;
	cin>>p;
	double cur = 1.0;
	if(n>=200){
		cout<<1<<endl;
		return 0;
	}
	rep(i,n){
		ans += cur * p;
		cur *= 1.0 - p;
	}
	
	cout<<fixed<<setprecision(10)<<ans<<endl;
	
	
	return 0;
}