stripMine

-- Programm for stripmining --

-- how many blocks should the main tunnel have --
print("How far should I stripmine?")
-- I fucked up the code on that so /2 lol --
local Xlength = io.read()
local length = Xlength/2
-- variable digging sizes, why not --
print("How deep should I dig in the sides?")
local depth = io.read()

-- digs a block and moves in that place --
local function dig()
    turtle.dig()
    turtle.forward()
end

-- uses dig(), but breaks block above, so players can walk --
local function digMain()
-- max = 3, cause we want only every 3rd block to be stripmined --
    for i=1, 3 do
        turtle.digUp()
        dig()
    end
end

-- makes a hole to the left by turning and using dig() times the amount of depth --
local function leftHole()
    turtle.digUp()
    turtle.up()
    turtle.turnLeft()
    for i=1, depth do
        dig()
    end
end

-- only uses dig() for depth times, since leftHole() positioned properly allready
local function rightHole()
    for i=1, depth do
        dig()
    end
end

-- turns the turtle around and gets him back to the center --
local function goBack()
    turtle.turnLeft()
    turtle.turnLeft()
    for i=1, depth do
        turtle.forward()
    end
end

-- repeated mining process times length --
for i=1, length do
    digMain()
    leftHole()
    goBack()
    rightHole()
    goBack()
    turtle.turnRight()
    turtle.down()
end