get_loop.ipynb

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   "source": [
    "def get_loop(bv_positions, ev_position):\n",
    "    def inner(loop):\n",
    "        if len(loop) > 3:\n",
    "            can_be_closed = len(get_possible_next_nodes(loop, [ev_position])) == 1\n",
    "            if can_be_closed: return loop\n",
    "        \n",
    "        not_visited = list(set(bv_positions) - set(loop))\n",
    "        possible_next_nodes = get_possible_next_nodes(loop, not_visited)\n",
    "        for next_node in possible_next_nodes:\n",
    "            new_loop = inner(loop + [next_node])\n",
    "            if new_loop: return new_loop\n",
    "    \n",
    "    return inner([ev_position])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 93,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[(2, 0), (2, 2), (1, 2), (1, 0)]"
      ]
     },
     "execution_count": 93,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "costs = [\n",
    "    [ 2, 2, 2, 1],\n",
    "    [10, 8, 5, 4],\n",
    "    [ 7, 6, 6, 8]\n",
    "]\n",
    "supply = [30, 70, 50]\n",
    "demand = [40, 30, 40, 40]\n",
    "bfs = north_west_corner(supply, demand)\n",
    "us, vs = get_us_and_vs(bfs, costs)\n",
    "ws = get_ws(bfs, costs, us, vs)\n",
    "can_be_improved(ws)\n",
    "\n",
    "ev_position = get_entering_variable_position(ws)\n",
    "get_loop([p for p, v in bfs], ev_position)"
   ]
  }
 ],
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