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

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