Turtle Digging Script

write("How Deep a Tunnel Should i dig? ")
local Num1 = tostring( read() )
write("How Wide Should i Dig? ")
local Num2 = tonumber( read() ) -1
write("How High should i Make The Tunnel? ")
local Num3 = tostring( read() ) -1

function dighole ()
    turtle.dig ()
    turtle.forward ()
end

function digUp ()
    turtle.digUp ()
    turtle.up ()
end

function check ()
    numbers = Num2
    if numbers%2 == 0 then
        odd = "true"
    else
        even = "true"
    end
end

check (number)
if odd == "true" then
    for i=1,Num1 do
        dighole()
        for i=1,Num3 do
            digUp ()
        end
        for i=1,Num3 do
            turtle.down ()
        end
        turtle.turnLeft ()
        for i=1,Num2 /2 do
            dighole ()
                for i=1,Num3 do
                    digUp ()
                end
                for i=1,Num3 do
                    turtle.down ()
                end
            end
        for i=1,Num2 do
            turtle.back ()
        end
        turtle.turnRight ()
        turtle.turnRight ()
        for i=1,Num2 /2 do
            dighole ()
                for i=1,Num3 do
                    digUp ()
                end
                for i=1,Num3 do
                    turtle.down ()
                end
            end
        for i=1,Num2 /2 do
            turtle.back ()
        end
        turtle.turnLeft ()
    end
    for i=1,Num1 do
        turtle.back ()
    end

else
    for i=1,Num1 do
        dighole()
        for i=1,Num3 do
            digUp ()
        end
        for i=1,Num3 do
            turtle.down ()
        end
        turtle.turnLeft ()
        for i=1,Num2 /2 +1 do
            dighole ()
                for i=1,Num3 do
                    digUp ()
                end
                for i=1,Num3 do
                    turtle.down ()
                end
            end
        for i=1,Num2 do
            turtle.back ()
        end
        turtle.turnRight ()
        turtle.turnRight ()
        for i=1,Num2 /2 do
            dighole ()
                for i=1,Num3 do
                    digUp ()
                end
                for i=1,Num3 do
                    turtle.down ()
                end
            end
        for i=1,Num2 /2 do
            turtle.back ()
        end
        turtle.turnLeft ()
    end
    for i=1,Num1 do
        turtle.back ()
    end
end

print("All Done")