#include <bits/stdc++.h>

using namespace std;
void fast_io() {
    ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
}

int main() {
    fast_io();
    int n;
    double r;
    cin >> n >> r;
    double ans = 0, cur = 100;
    for (int i = 0; i < n; i++) {
        ans += cur;
        cur *= (1 - r);
    }
    cout << setprecision(16) << fixed << ans << endl;
}