function annotate(field)
    afield = []
    for x ∈ 1:length(field)
        line = ""
        for y ∈ 1:length(field[x])
            el = field[x][y]
            if el == '*'
                line = "$line$el"
                continue
            end
            stars = 0
            if x > 1
                stars += count(c -> c == '*', field[x - 1][max(y - 1, 1):min(y + 1, length(field[x]))])
            end
            stars += count(c -> c == '*', field[x][max(y - 1, 1):min(y + 1, length(field[x]))])
            if x < length(field)
                stars += count(c -> c == '*', field[x + 1][max(y - 1, 1):min(y + 1, length(field[x]))])
            end
            ch = stars == 0 ? " " : "$stars"
            line = "$line$ch"
        end
        append!(afield, [line])
    end
    afield
end