destroyFloor

local length = 61
local width = 61

local function refuel()
    if turtle.getFuelLevel() < 50 then
        local prev = turtle.getSelectedSlot()
        turtle.select(1)
        if not turtle.refuel(4) then
            print('Need more fuel')
            while not turtle.refuel(4) do
                sleep(3)
            end
        end
        turtle.select(prev)
    end
end

local function tryForwards()
    refuel()
    while not turtle.forward() do
        if turtle.detect() then
            turtle.dig()
            sleep(.5)
            while turtle.detect() do
                turtle.dig()
                sleep(.5)
            end
        elseif turtle.attack() then
        else
            sleep(1)
        end
    end
end

local function turnAround(i)
    turtle.placeDown()
    if i%2 == 1 then
        turtle.turnRight()
        tryForwards()
        turtle.turnRight()
    else
        turtle.turnLeft()
        tryForwards()
        turtle.turnLeft()
    end
end
turtle.select(2)
for i = 1, length-1, 1 do
    for j = 1, width-1, 1 do
        refuel()
        tryForwards()
    end
    turnAround(i)
end