Quick Sort.ipynb

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      "Sorted array: [1, 5, 7, 8, 9, 10]\n"
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    "#########################################\n",
    "# Quick Sort using Python\n",
    "# By Giriraj Vaishnav\n",
    "#########################################\n",
    " \n",
    "# This Function handles sorting part of quick sort\n",
    "# start and end points to first and last element of\n",
    "# an array respectively\n",
    "def partition(start, end, array):\n",
    "     \n",
    "    # Initializing pivot's index to start\n",
    "    pivot_index = start\n",
    "    pivot = array[pivot_index]\n",
    "     \n",
    "    # This loop runs till start pointer crosses\n",
    "    # end pointer, and when it does we swap the\n",
    "    # pivot with element on end pointer\n",
    "    while start < end:\n",
    "         \n",
    "        # Increment the start pointer till it finds an\n",
    "        # element greater than  pivot\n",
    "        while start < len(array) and array[start] <= pivot:\n",
    "            start += 1\n",
    "             \n",
    "        # Decrement the end pointer till it finds an\n",
    "        # element less than pivot\n",
    "        while array[end] > pivot:\n",
    "            end -= 1\n",
    "         \n",
    "        # If start and end have not crossed each other,\n",
    "        # swap the numbers on start and end\n",
    "        if(start < end):\n",
    "            array[start], array[end] = array[end], array[start]\n",
    "     \n",
    "    # Swap pivot element with element on end pointer.\n",
    "    # This puts pivot on its correct sorted place.\n",
    "    array[end], array[pivot_index] = array[pivot_index], array[end]\n",
    "    \n",
    "    # Returning end pointer to divide the array into 2\n",
    "    return end\n",
    "     \n",
    "# The main function that implements QuickSort\n",
    "def quick_sort(start, end, array):\n",
    "     \n",
    "    if (start < end):\n",
    "         \n",
    "        # p is partitioning index, array[p]\n",
    "        # is at right place\n",
    "        p = partition(start, end, array)\n",
    "         \n",
    "        # Sort elements before partition\n",
    "        # and after partition\n",
    "        quick_sort(start, p - 1, array)\n",
    "        quick_sort(p + 1, end, array)\n",
    "         \n",
    "# Driver code\n",
    "array = [ 10, 7, 8, 9, 1, 5 ]\n",
    "quick_sort(0, len(array) - 1, array)\n",
    " \n",
    "print(f'Sorted array: {array}')"
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