lighter

function portal()

    for i = 1, x do

    for i = 1, y - 1 do

        for i = 1, z do
            turtle.place()
            turtle.turnRight()
            turtle.place()
            turtle.turnLeft()
            shell.run("go back 3")

        end

        turtle.place()
        turtle.turnRight()
        shell.run("go back 3")
        turtle.turnLeft()

        for i = 1, z *3 do

        turtle.forward()

        end

    end

            for i = 1, z do

            turtle.place()
            turtle.turnRight()
            turtle.place()
            turtle.turnLeft()
            shell.run("go back 3")

        end

        turtle.place()
        turtle.turnRight()
        shell.run("go back 3")
        turtle.turnLeft()

            for i = 1, z do

                shell.run("go forward 2")
                turtle.turnRight()
                turtle.place()
                turtle.turnLeft()
                turtle.forward()

            end

            shell.run("go forward 2")
            turtle.turnRight()

            for i = 1, y * 3 do

                turtle.forward()

            end

            turtle.turnLeft()

            shell.run("go up 4")
            turtle.back()
            turtle.back()

            s = s + 1
            turtle.select(s)

    end

    shell.run("go forward 2")

    for i = 1, x*4 do

        turtle.down()

    end

    shell.run("go down 2")
    turtle.turnLeft()
    turtle.back()
    turtle.turnLeft()

end

print("Enter height:")
x = io.read()
print("Enter width:")
y = io.read()
print("Enter depth:")
z = io.read()

s = 1

turtle.up()
turtle.turnRight()
turtle.forward()
turtle.turnRight()
turtle.up()
turtle.back()
turtle.back()
portal()