DigMass

function moveDown(blocks)
    for i=1,blocks do
        turtle.down()
    end
end


function digAllUp()
    local i = 0
    while (turtle.detectUp()) do
        i = i + 1
        turtle.digUp()
        turtle.up()
    end
    moveDown(i)
end

function digAllLine(amount)
    for i=1,amount do
        digAllUp()
        turtle.dig()
        turtle.forward()
    end
    digAllUp()
end

function turnNum(num)
    if (num == 1) then
        turtle.turnRight()
        turtle.dig()
        turtle.forward()
        turtle.turnRight()
    else
        turtle.turnLeft()
        turtle.dig()
        turtle.forward()
        turtle.turnLeft()
    end
end

function main(width, length)
    local side = 1
    for i=1,length do
        digAllLine(width)
        turnNum(side)
        side = side * -1
    end
end

print("width(forward):")
local width = tonumber(read())
print("length(right):")
local length = tonumber(read())

main(width, length)