Bridge building code V.2

function stairUp()

turtle.select(1)
turtle.up()
turtle.forward()
turtle.select(1)
turtle.placeDown()
turtle.place()
turtle.turnLeft()
turtle.forward()
turtle.turnRight()
turtle.placeDown()
turtle.place()
turtle.turnRight()
turtle.forward()
turtle.forward()
turtle.turnLeft()
turtle.placeDown()
turtle.place()
turtle.up()
turtle.forward()
turtle.forward()
end

function platform()

turtle.select(2)
for i = 2, times do
turtle.placeDown()
turtle.forward()

end
end

function stairDown()

turtle.select(1)
function stairDown()
turtle.turnRight()
turtle.turnRight()
turtle.down()
turtle.placeDown()
turtle.place()
turtle.turnLeft()
turtle.forward()
turtle.turnRight()
turtle.placeDown()
turtle.place()
turtle.turnLeft()
turtle.forward()
turtle.turnRight()
turtle.placedown()
turtle.place()
turtle.turnRight()
turtle.turnRight()
turtle.forward()
turtle.down()
end

print("WELCOME TO THE BRIDGE BUILDING PROGRAM")
print("PLEASE PUT STAIRS IN THE FIRST SLOT")
print("PUT THE MAIN BRIDGE MATERIALS IN THE SECOUND SLOT")
term.write("HOW LONG IS THE DESIRED BRIDGE? ")
times = read()

stairUp()
platform()
turtle.placeDown()
turtle.turnLeft()
turtle.forward()
turtle.turnLeft()
platform()
turtle.placeDown()
turtle.turnRight()
turtle.forward()
turtle.turnRight()
platform()
turtle.placeDown()
turtle.forward()
turtle.forward()
stairDown()
print("BRIDGE COMPLETE")