Heap Sort (Max Heapify).ipynb

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   "source": [
    "def max_heapify(arr, i, arr_size):\n",
    "    left, right, largest = i * 2, i * 2 + 1, i\n",
    "    if left < arr_size and arr[left] > arr[i]:\n",
    "        largest = left\n",
    "    if right < arr_size and arr[right] > arr[largest]:\n",
    "        largest = right\n",
    "    if largest != i:\n",
    "        arr[i], arr[largest] = arr[largest], arr[i]\n",
    "        max_heapify(arr, largest, arr_size)"
   ]
  },
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   "cell_type": "code",
   "execution_count": 14,
   "metadata": {},
   "outputs": [],
   "source": [
    "def heap_sort(arr, arr_size):\n",
    "    for i in range(int(arr_size / 2), -1, -1):\n",
    "        max_heapify(arr, i, arr_size)\n",
    "    for i in range(arr_size - 1, 0, -1):\n",
    "        arr[0], arr[i] = arr[i], arr[0]\n",
    "        max_heapify(arr, 0, i)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {},
   "outputs": [],
   "source": [
    "a = [5,4,3,2,1]\n",
    "# heap_sort(a, len(a))\n",
    "max_heapify(a, 0, len(a))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 16,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[5, 4, 3, 2, 1]"
      ]
     },
     "execution_count": 16,
     "metadata": {},
     "output_type": "execute_result"
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   "source": [
    "a"
   ]
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  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
  }
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