turtle

function digF()
    while not turtle.forward() do
        turtle.dig()
    end
end

function digU()
    while not turtle.up() do
        turtle.digUp()
    end
end

function digD()
    while not turtle.down() do
        turtle.digDown()
    end
end

function detectU()
    while turtle.detectUp() do
        turtle.digUp()
    end
end

function detectD()
    while turtle.detectDown() do
        turtle.digDown()
    end
end

function tF()
    if turtle.getFuelLevel()>0, than turtle.getFuelLevel()==0  do
        turtle.refuel()
    end
end

print("Enter lenght vaule of corridor")
local lenght=read()/2

for i=1,lenght do
tF()