function task0(file)
    rand_numbers = readline(file) |> x -> split(x, ",") .|> x -> parse(Int, x)

    boards = []

    while !eof(file)
        push!(boards,
            [readline(file, keep = true) for i = 1:6] |>
            x -> vcat("[", x, "]") |>
                 join |>
                 Meta.parse |>
                 eval |>
                 x -> convert(Array{Union{Int,Missing},2}, x)
        )
    end

    for number in rand_numbers
        for board in boards
            board[(board.==number).&map(!, board .=== missing)] .= missing

            if any(map(!, (board .=== missing)) * ones(size(board, 2)) .== 0) ||
               any(map(!, (board .=== missing))' * ones(size(board, 1)) .== 0)

                return sum(skipmissing(board)) * number
            end
        end
    end

    boards
end

##

println("Day 04 – Task 1 – Case 0")
open(task0, "day04\\data\\case00.txt") |> println

println("Day 04 – Task 1 – Case 1")
open(task0, "day04\\data\\case01.txt") |> println

##

function task1(file)
    rand_numbers = readline(file) |> x -> split(x, ",") .|> x -> parse(Int, x)

    boards = []

    while !eof(file)
        push!(boards,
            [readline(file, keep = true) for i = 1:6] |>
            x -> vcat("[", x, "]") |>
                 join |>
                 Meta.parse |>
                 eval |>
                 x -> convert(Array{Union{Int,Missing},2}, x)
        )
    end

    for number in rand_numbers
        toremove = []

        for (i, board) in enumerate(boards)
            board[(board.==number).&map(!, board .=== missing)] .= missing

            if any(map(!, (board .=== missing)) * ones(size(board, 2)) .== 0) ||
               any(map(!, (board .=== missing))' * ones(size(board, 1)) .== 0)

                if length(boards) == 1
                    return sum(skipmissing(board)) * number
                else
                    push!(toremove, i)
                end
            end
        end

        boards = toremove |> x -> deleteat!(boards, x)
    end

    boards
end

##

println("Day 04 – Task 2 – Case 0")
open(task1, "day04\\data\\case00.txt") |> println

println("Day 03 – Task 2 – Case 1")
open(task1, "day04\\data\\case01.txt") |> println