From 5f29d2d61a17fddaa26235e53410fc26fb0e73b1 Mon Sep 17 00:00:00 2001
From: TanCodes <barvitanmay20@gmail.com>
Date: Sat, 9 Oct 2021 20:28:09 +0530
Subject: [PATCH] Python Dsa added #1 array

---
 Python/Python_DSA/#1 Array.ipynb              | 572 ++++++++++++++++++
 .../#1 Array-checkpoint.ipynb                 | 572 ++++++++++++++++++
 2 files changed, 1144 insertions(+)
 create mode 100644 Python/Python_DSA/#1 Array.ipynb
 create mode 100644 Python/Python_DSA/.ipynb_checkpoints/#1 Array-checkpoint.ipynb

diff --git a/Python/Python_DSA/#1 Array.ipynb b/Python/Python_DSA/#1 Array.ipynb
new file mode 100644
index 0000000..4c37a30
--- /dev/null
+++ b/Python/Python_DSA/#1 Array.ipynb	
@@ -0,0 +1,572 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# <center>🔰 Arrays in Python"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### An array is a collection of items stored at contiguous memory locations.\n",
+    "\n",
+    "- Python arrays are a data structure like lists. \n",
+    "- They contain a number of objects that can be of different data types.\n",
+    "- Python has a number of built-in data structures, such as arrays.\n",
+    "- Index starts with 0.\n",
+    "- We can access each element via its index.\n",
+    "- The length of the array defines the capacity to store the elements."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "![](https://ik.imagekit.io/tfme5aczhhf/contributiojn/mceu_61653743011611745415316_1__OE7LeT5_K.jpg)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Some of the basic operations supported by an array are as follows:\n",
+    "\n",
+    "- [x] Traverse - It prints all the elements one by one. <br>\n",
+    "- [x] Insertion - It adds an element at the given index. <br>\n",
+    "- [x] Deletion - It deletes an element at the given index.<br>\n",
+    "- [x] Search - It searches an element using the given index or by the value.<br>\n",
+    "- [x] Update - It updates an element at the given index.<br>"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "##### Create basic array"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "['1st', '2nd', '3rd']"
+      ]
+     },
+     "execution_count": 1,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "# Simple way to create an array.\n",
+    "\n",
+    "array = [\"1st\", \"2nd\", \"3rd\"]\n",
+    "#prints: ['1st', '2nd', '3rd']\n",
+    "array"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "array('d', [1.1, 3.5, 4.5])\n"
+     ]
+    }
+   ],
+   "source": [
+    "# Also can be created using array module\n",
+    "\n",
+    "import array as arr\n",
+    "a = arr.array('d', [1.1, 3.5, 4.5])\n",
+    "print(a)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Working with Arrays"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "['data1', 'data2', 3, 4, 5]"
+      ]
+     },
+     "execution_count": 3,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "# created one small array\n",
+    "# -------------------------------------------------------------------\n",
+    "arr = [\"data1\",\"data2\", 3, 4, 5]\n",
+    "arr"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "3"
+      ]
+     },
+     "execution_count": 4,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "#acessing the array - We are passing the index of an array. Index starts with 0\n",
+    "# -------------------------------------------------------------------\n",
+    "arr[2]"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "5"
+      ]
+     },
+     "execution_count": 5,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "# len() gives the length of our array i.e 6 which len starts with 1.\n",
+    "# -------------------------------------------------------------------\n",
+    "len(arr)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "['data0', 'data2', 3, 4, 5]"
+      ]
+     },
+     "execution_count": 6,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "# replacing (updating) the data of an array\n",
+    "# -> We updated the index 0 data with new data i.e \"data0\"\n",
+    "# -------------------------------------------------------------------\n",
+    "arr[0] = \"data0\"\n",
+    "arr"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "['data0', 'data2', 3, 4, 5, 'last_data']"
+      ]
+     },
+     "execution_count": 7,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "#APPEND - adds the element to the last postion of the array\n",
+    "# -------------------------------------------------------------------\n",
+    "arr.append(\"last_data\")\n",
+    "arr"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 8,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "['data0', 3, 4, 5, 'last_data']"
+      ]
+     },
+     "execution_count": 8,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "# removes the data from an array which is \"data2\"\n",
+    "# -------------------------------------------------------------------\n",
+    "arr.remove(\"data2\")\n",
+    "arr"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 9,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "4"
+      ]
+     },
+     "execution_count": 9,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "# pop means to remove the data from an array at given index\n",
+    "# -------------------------------------------------------------------\n",
+    "arr.pop(2)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 10,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "['data0', 3, 5, 'last_data']"
+      ]
+     },
+     "execution_count": 10,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "# so this is now our array after popping the data from index 2\n",
+    "# -------------------------------------------------------------------\n",
+    "arr"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 11,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "data0\n",
+      "3\n",
+      "5\n",
+      "last_data\n"
+     ]
+    }
+   ],
+   "source": [
+    "# Looping through the array\n",
+    "# -------------------------------------------------------------------\n",
+    "for items in arr:\n",
+    "    print(items)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 12,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "['last_data', 5, 3, 'data0']"
+      ]
+     },
+     "execution_count": 12,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "# it reverses the array\n",
+    "# -------------------------------------------------------------------\n",
+    "arr.reverse()\n",
+    "arr"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 13,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# clear, removes all the array data and makes it empty.\n",
+    "# -------------------------------------------------------------------\n",
+    "arr.clear()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 14,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "[]"
+      ]
+     },
+     "execution_count": 14,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "arr  #so our array is now empty after using clear()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Q) Find the second largest number in an array"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 15,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "a = [1,3,4,5,0,2]"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### could array be empyt?\n",
+    "yes . 2nd largest(a) should return None."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### could array have only one element?\n",
+    "yes. 2nd largest(a) should return None."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### what if we had say [2,2,1]\n",
+    "yes . 2nd largest(a) should return none . then 2nd largest(a) should return 2"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 16,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "def second_largest(given_list):\n",
+    "    largest = None\n",
+    "    second_largest = None\n",
+    "    for current_number in given_list:\n",
+    "        if largest == None:\n",
+    "            largest = current_number\n",
+    "        elif current_number > largest:\n",
+    "            second_largest = largest\n",
+    "            largest = current_number\n",
+    "        elif second_largest == None:\n",
+    "            second_largest = current_number\n",
+    "        elif current_number > second_largest:\n",
+    "            second_largest = current_number\n",
+    "    return second_largest"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "##### Test cases"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 17,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Max is 4\n"
+     ]
+    }
+   ],
+   "source": [
+    "print(\"Max is\", second_largest([1,3,4,5,0,2]))"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 18,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Max is -2\n"
+     ]
+    }
+   ],
+   "source": [
+    "print(\"Max is\",second_largest([-2,-1]))"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 19,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Max is 2\n"
+     ]
+    }
+   ],
+   "source": [
+    "print(\"Max is\",second_largest([2,2,1]))"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 20,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Max is None\n"
+     ]
+    }
+   ],
+   "source": [
+    "print(\"Max is\",second_largest([2]))"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 21,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Max is None\n"
+     ]
+    }
+   ],
+   "source": [
+    "print(\"Max is\",second_largest([]))"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## `Find me around the web 🌎:`\n",
+    "\n",
+    "\n",
+    "* <a href=\"http://tancodes.atspace.cc/\" target=\"blank\">Portfolio </a>\n",
+    "* <a href=\"https://instagram.com/_tancodes_\" target=\"blank\">   Instagram </a>\n",
+    "* <a href=\"https://www.linkedin.com/in/tanmay-barvi-2a0206126/\" target=\"blank\">  LinkedIn </a>\n",
+    "* <a href=\"https://twitter.com/tancodes\" target=\"blank\"> Twitter </a>\n",
+    "* <a href=\"https://www.behance.net/tanmaybrv\" target=\"blank\"> Behance </a>\n",
+    "* <a href=\"https://www.youtube.com/channel/UC370GTtJnvWs8wDH9UXoBzQ?view_as=subscriber\" target=\"blank\">  YouTube  </a> \n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "\n",
+    "###  <center> HAPPY CODING WITH PYTHON \n",
+    "![](https://img.shields.io/badge/Python-FFD43B?style=for-the-badge&logo=python&logoColor=darkgreen)\n",
+    "![](https://forthebadge.com/images/badges/built-with-love.svg)\n",
+    "<p align=\"center\">\n",
+    "  <img src=\"https://raw.githubusercontent.com/TanCodes/readme_img/main/ezgif-6-c5c72c3f9fb3.gif\">\n",
+    "</p>"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3 (ipykernel)",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.9.0"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 4
+}
diff --git a/Python/Python_DSA/.ipynb_checkpoints/#1 Array-checkpoint.ipynb b/Python/Python_DSA/.ipynb_checkpoints/#1 Array-checkpoint.ipynb
new file mode 100644
index 0000000..4c37a30
--- /dev/null
+++ b/Python/Python_DSA/.ipynb_checkpoints/#1 Array-checkpoint.ipynb	
@@ -0,0 +1,572 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# <center>🔰 Arrays in Python"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### An array is a collection of items stored at contiguous memory locations.\n",
+    "\n",
+    "- Python arrays are a data structure like lists. \n",
+    "- They contain a number of objects that can be of different data types.\n",
+    "- Python has a number of built-in data structures, such as arrays.\n",
+    "- Index starts with 0.\n",
+    "- We can access each element via its index.\n",
+    "- The length of the array defines the capacity to store the elements."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "![](https://ik.imagekit.io/tfme5aczhhf/contributiojn/mceu_61653743011611745415316_1__OE7LeT5_K.jpg)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Some of the basic operations supported by an array are as follows:\n",
+    "\n",
+    "- [x] Traverse - It prints all the elements one by one. <br>\n",
+    "- [x] Insertion - It adds an element at the given index. <br>\n",
+    "- [x] Deletion - It deletes an element at the given index.<br>\n",
+    "- [x] Search - It searches an element using the given index or by the value.<br>\n",
+    "- [x] Update - It updates an element at the given index.<br>"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "##### Create basic array"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "['1st', '2nd', '3rd']"
+      ]
+     },
+     "execution_count": 1,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "# Simple way to create an array.\n",
+    "\n",
+    "array = [\"1st\", \"2nd\", \"3rd\"]\n",
+    "#prints: ['1st', '2nd', '3rd']\n",
+    "array"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "array('d', [1.1, 3.5, 4.5])\n"
+     ]
+    }
+   ],
+   "source": [
+    "# Also can be created using array module\n",
+    "\n",
+    "import array as arr\n",
+    "a = arr.array('d', [1.1, 3.5, 4.5])\n",
+    "print(a)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### Working with Arrays"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "['data1', 'data2', 3, 4, 5]"
+      ]
+     },
+     "execution_count": 3,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "# created one small array\n",
+    "# -------------------------------------------------------------------\n",
+    "arr = [\"data1\",\"data2\", 3, 4, 5]\n",
+    "arr"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "3"
+      ]
+     },
+     "execution_count": 4,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "#acessing the array - We are passing the index of an array. Index starts with 0\n",
+    "# -------------------------------------------------------------------\n",
+    "arr[2]"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "5"
+      ]
+     },
+     "execution_count": 5,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "# len() gives the length of our array i.e 6 which len starts with 1.\n",
+    "# -------------------------------------------------------------------\n",
+    "len(arr)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 6,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "['data0', 'data2', 3, 4, 5]"
+      ]
+     },
+     "execution_count": 6,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "# replacing (updating) the data of an array\n",
+    "# -> We updated the index 0 data with new data i.e \"data0\"\n",
+    "# -------------------------------------------------------------------\n",
+    "arr[0] = \"data0\"\n",
+    "arr"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "['data0', 'data2', 3, 4, 5, 'last_data']"
+      ]
+     },
+     "execution_count": 7,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "#APPEND - adds the element to the last postion of the array\n",
+    "# -------------------------------------------------------------------\n",
+    "arr.append(\"last_data\")\n",
+    "arr"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 8,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "['data0', 3, 4, 5, 'last_data']"
+      ]
+     },
+     "execution_count": 8,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "# removes the data from an array which is \"data2\"\n",
+    "# -------------------------------------------------------------------\n",
+    "arr.remove(\"data2\")\n",
+    "arr"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 9,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "4"
+      ]
+     },
+     "execution_count": 9,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "# pop means to remove the data from an array at given index\n",
+    "# -------------------------------------------------------------------\n",
+    "arr.pop(2)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 10,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "['data0', 3, 5, 'last_data']"
+      ]
+     },
+     "execution_count": 10,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "# so this is now our array after popping the data from index 2\n",
+    "# -------------------------------------------------------------------\n",
+    "arr"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 11,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "data0\n",
+      "3\n",
+      "5\n",
+      "last_data\n"
+     ]
+    }
+   ],
+   "source": [
+    "# Looping through the array\n",
+    "# -------------------------------------------------------------------\n",
+    "for items in arr:\n",
+    "    print(items)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 12,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "['last_data', 5, 3, 'data0']"
+      ]
+     },
+     "execution_count": 12,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "# it reverses the array\n",
+    "# -------------------------------------------------------------------\n",
+    "arr.reverse()\n",
+    "arr"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 13,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# clear, removes all the array data and makes it empty.\n",
+    "# -------------------------------------------------------------------\n",
+    "arr.clear()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 14,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "[]"
+      ]
+     },
+     "execution_count": 14,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "arr  #so our array is now empty after using clear()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Q) Find the second largest number in an array"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 15,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "a = [1,3,4,5,0,2]"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### could array be empyt?\n",
+    "yes . 2nd largest(a) should return None."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### could array have only one element?\n",
+    "yes. 2nd largest(a) should return None."
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "#### what if we had say [2,2,1]\n",
+    "yes . 2nd largest(a) should return none . then 2nd largest(a) should return 2"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 16,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "def second_largest(given_list):\n",
+    "    largest = None\n",
+    "    second_largest = None\n",
+    "    for current_number in given_list:\n",
+    "        if largest == None:\n",
+    "            largest = current_number\n",
+    "        elif current_number > largest:\n",
+    "            second_largest = largest\n",
+    "            largest = current_number\n",
+    "        elif second_largest == None:\n",
+    "            second_largest = current_number\n",
+    "        elif current_number > second_largest:\n",
+    "            second_largest = current_number\n",
+    "    return second_largest"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "##### Test cases"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 17,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Max is 4\n"
+     ]
+    }
+   ],
+   "source": [
+    "print(\"Max is\", second_largest([1,3,4,5,0,2]))"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 18,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Max is -2\n"
+     ]
+    }
+   ],
+   "source": [
+    "print(\"Max is\",second_largest([-2,-1]))"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 19,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Max is 2\n"
+     ]
+    }
+   ],
+   "source": [
+    "print(\"Max is\",second_largest([2,2,1]))"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 20,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Max is None\n"
+     ]
+    }
+   ],
+   "source": [
+    "print(\"Max is\",second_largest([2]))"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 21,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Max is None\n"
+     ]
+    }
+   ],
+   "source": [
+    "print(\"Max is\",second_largest([]))"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## `Find me around the web 🌎:`\n",
+    "\n",
+    "\n",
+    "* <a href=\"http://tancodes.atspace.cc/\" target=\"blank\">Portfolio </a>\n",
+    "* <a href=\"https://instagram.com/_tancodes_\" target=\"blank\">   Instagram </a>\n",
+    "* <a href=\"https://www.linkedin.com/in/tanmay-barvi-2a0206126/\" target=\"blank\">  LinkedIn </a>\n",
+    "* <a href=\"https://twitter.com/tancodes\" target=\"blank\"> Twitter </a>\n",
+    "* <a href=\"https://www.behance.net/tanmaybrv\" target=\"blank\"> Behance </a>\n",
+    "* <a href=\"https://www.youtube.com/channel/UC370GTtJnvWs8wDH9UXoBzQ?view_as=subscriber\" target=\"blank\">  YouTube  </a> \n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "\n",
+    "###  <center> HAPPY CODING WITH PYTHON \n",
+    "![](https://img.shields.io/badge/Python-FFD43B?style=for-the-badge&logo=python&logoColor=darkgreen)\n",
+    "![](https://forthebadge.com/images/badges/built-with-love.svg)\n",
+    "<p align=\"center\">\n",
+    "  <img src=\"https://raw.githubusercontent.com/TanCodes/readme_img/main/ezgif-6-c5c72c3f9fb3.gif\">\n",
+    "</p>"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3 (ipykernel)",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.9.0"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 4
+}