ComputerCraft maze generator

location=vector.new(1,0)
dir=0
tArgs={...}
if #tArgs<1 then
print("Usage: mazegen <width> [length]")
return
end
width=tonumber(tArgs[1])
height=tonumber(tArgs[2]) or width
print("Making maze ",width,"x",height)
cells={}

for i=0,width+1 do
 cells[i]={}
 for j=0,height+1 do
  cells[i][j]={visited=true,parent=vector.new(),pos=vector.new(i,j),finish=false}
 end
end

for i=1,width do
for j=1,height do
 cells[i][j].visited=false
end
end

cells[width][height+1].finish=true
cells[width][height+1].visited=false

function go(goto)
 local goDir=goto-location
 local tardir=0
 if goDir.x>0 then
  tardir=1
 elseif goDir.x<0 then
  tardir=3
 end
 if goDir.y>0 then
  tardir=0
 elseif goDir.y<0 then
  tardir=2
 end
 while dir~=tardir do
  turtle.turnRight()
  dir=(dir+1)%4
 end
 print(tardir)
 turtle.dig()
 turtle.forward()
 turtle.digUp()
 turtle.dig()
 turtle.forward()
 turtle.digUp()
 cells[goto.x][goto.y].visited=true
 location=goto
end

function mazegen(nextpoint)
 cells[nextpoint.x][nextpoint.y].parent=location
 print("Moving forward")
 go(nextpoint)
 if cells[location.x][location.y].finish==true then
  turtle.placeUp()
  print("Found finish")
 else
  local neighbours={cells[nextpoint.x-1][nextpoint.y],cells[nextpoint.x+1][nextpoint.y],cells[nextpoint.x][nextpoint.y-1],cells[nextpoint.x][nextpoint.y+1]}
  local unvisited={}
  for i,v in ipairs(neighbours) do
   if v.visited==false then
    table.insert(unvisited,v)
   end
  end
  while #unvisited>0 do
   local randomnum=math.random(1,#unvisited)
   if cells[unvisited[randomnum].pos.x][unvisited[randomnum].pos.y].visited==false then
    print("New branch at "..tostring(unvisited[randomnum].pos))
    mazegen(unvisited[randomnum].pos)
   end
   table.remove(unvisited,randomnum)
   print(#unvisited .." left")
  end
 end
 print("Backtracking to "..tostring(cells[location.x][location.y].parent))
 go(cells[location.x][location.y].parent)
end

mazegen(vector.new(1,1))
turtle.turnRight()
turtle.turnRight()
file=fs.open("mazeblueprint","w")
file.write(textutils.serialize(cells))
file.close()