/* Problem URL: https://codeforces.com/gym/102644/problem/A */

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template <class T, class comp = less<>>
using ordered_set = tree<T, null_type , comp , rb_tree_tag , tree_order_statistics_node_update>;

#define V vector

#define rmin(a, b) a = min(a, b)
#define rmax(a, b) a = max(a, b)

#define rep(i, lim) for (int i = 0; i < (lim); i++)
#define nrep(i, s, lim) for (int i = s; i < (lim); i++)

#define repv(i, v) for (auto &i : (v))
#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
#define sortv(v) sort(v.begin(), v.end())
#define all(v) (v).begin(), (v).end()

using vi = vector<int>;
using vvi = vector<vi>;
using vvvi = vector<vvi>;
using vvvvi = vector<vvvi>;

using ll = long long;

using vl = vector<ll>;
using vvl = vector<vl>;
using vvvl = vector<vvl>;
using vvvvl = vector<vvvl>;

template<class v>
auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
    os << vec[0];
    for (size_t i = 1; i < vec.size(); i++) {
        os << ' ' << vec[i];
    }
    os << '\n';
    return os;
}

template<class v>
auto operator>>(istream &is, vector<v> &vec)->istream& {
    for (auto &i : vec) {
        is >> i;
    }
    return is;
}

template<class v>
auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
    for (auto &i : vec) {
        os << i[0];
        for (size_t j = 1; j < i.size(); j++) {
            os << ' ' << i[j];
        }
        os << '\n';
    }
    return os;
}

template<class v>
auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
    for (auto &i : vec) {
        for (auto &j : i) {
            is >> j;
        }
    }
    return is;
}

const int oo = INT32_MAX >> 1;
const ll OO = INT64_MAX >> 1;


void pre()
{

}

#define TEST 0

void solve()
{
    ll n;
    long double p;
    cin >> n >> p;

    // long double h = 1;
    // long double s = 1;
    //
    // rep(i, n) {
    //     long double th = h * (1 - p) + s * p;
    //     long double ts = h * p + s * (p - 1);
    //     h = th;
    //     s = ts;
    // }

    V<V<long double>> mat = {{1}, 
                             {0}};

    auto mul = [&](V<V<long double>> &a, V<V<long double>> &b) {
        V<V<long double>> c(a.size(), V<long double>(b[0].size()));

        rep(i, c.size()) {
            rep(j, c[0].size()) {
                rep(k, b.size()) {
                    c[i][j] += a[i][k] * b[k][j];
                }
            }
        }

        return c;
    };

    V<V<long double>> prob = {{1 - p, p},
                              {p, 1 - p}};

    rep(i, 30) {
        if ((n >> i) & 1) {
            mat = mul(prob, mat);
        }

        prob = mul(prob, prob);
    }

    cout << fixed << setprecision(10) << mat[0][0] << '\n';
}

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    pre();

    int t;
    (TEST && cin >> t) || (t = 1);
    while (t--) {
        solve();
    }
}