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


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

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

    double ans = 0, q = 1.0;
    for(int i = 0; i < n; ++i){
        ans += q * p;
        q *= 1 - p;
    }
    cout << setprecision(16) << ans << endl;

    return 0;
}