open System

let n, m =
    let l = Console.ReadLine().Split(' ') |> Array.map int
    l.[0], l.[1]

let ans =
    let acProb =
        [1 .. m]
        |> List.fold (fun acc _ -> acc * 0.5) 1.
    let tleProb =
        1. - acProb

    let n = n |> float
    let m = m |> float
    let submitCost =
        100. * (n - m) + 1900. * m

    let expectation k prob = submitCost * k * prob

    [   let mutable k = 1.
        let mutable prob = acProb
        yield (expectation k prob)

        while (expectation k prob) > 0.01 do
            k <- k + 1.
            prob <- tleProb * prob
            yield (expectation k prob)]
    |> List.sum
    |> Math.Ceiling
    |> int

ans |> Console.WriteLine
