{
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"worksheets": [
{
"cells": [
{
"cell_type": "heading",
"level": 1,
"metadata": {},
"source": [
"Chapter 18: Java Collections"
]
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 18.1, page no. 348"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\"\"\"\n",
"Note: there is no such class in Python. We will perform normal operations on array\n",
"\"\"\"\n",
"\n",
"arrayList = []\n",
"print \"Initial size of arrayList: \", len(arrayList)\n",
"arrayList.append(\"A\")\n",
"arrayList.append(\"B\")\n",
"arrayList.append(\"C\")\n",
"arrayList.append(\"D\")\n",
"arrayList.insert(2, \"E\")\n",
"print \"Changed contents of arraylist by adding element at the given index: \", arrayList\n",
"arrayList.pop(3)\n",
"arrayList.remove(\"A\")\n",
"print \"Changed contents of arraylist by removing element from the list: \", arrayList"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Initial size of arrayList: 0\n",
"Changed contents of arraylist by adding element at the given index: ['A', 'B', 'E', 'C', 'D']\n",
"Changed contents of arraylist by removing element from the list: ['B', 'E', 'D']\n"
]
}
],
"prompt_number": 9
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 18.2, page no. 349"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\"\"\"\n",
"Note: There is no such collection in Python. We will dqueue instead, which is very much similar\n",
"\"\"\"\n",
"\n",
"from collections import deque\n",
"\n",
"d = deque()\n",
"\n",
"class MyStack():\n",
" def push1(self, o):\n",
" d.appendleft(o)\n",
" def push2(self, o):\n",
" d.append(o)\n",
" def bottom(self):\n",
" return d.pop()\n",
" def pop(self):\n",
" return d.popleft()\n",
"\n",
"class Car():\n",
" car1 = \"Benz\"\n",
" car2 = \"Toyoto\"\n",
" car3 = \"Qualis\"\n",
" car4 = \"Santro\"\n",
"\n",
"class Bird():\n",
" bird1 = \"parrot\"\n",
" bird2 = \"duck\"\n",
" bird3 = \"raven\"\n",
"\n",
"myCar = Car()\n",
"myBird = Bird()\n",
"s = MyStack()\n",
"s.push1(myCar.car1)\n",
"s.push2(myBird.bird3)\n",
"myCar = s.pop()\n",
"print \"The first element in the list: \", myCar\n",
"print \"The last element in the list: \", myBird.bird3"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The first element in the list: Benz\n",
"The last element in the list: raven\n"
]
}
],
"prompt_number": 15
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 18.3, page no. 351"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\"\"\"\n",
"Note: there is no collection hash set in Python. We will solve it in different manner\n",
"\"\"\"\n",
"\n",
"hs = set()\n",
"\n",
"hs.add(\"D\")\n",
"hs.add(\"A\")\n",
"hs.add(\"C\")\n",
"hs.add(\"B\")\n",
"hs.add(\"E\")\n",
"\n",
"#answer will differ due to difference in built-in techniques\n",
"print \"The elements available in the hash set are: \", hs"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The elements available in the hash set are: set(['A', 'C', 'B', 'E', 'D'])\n"
]
}
],
"prompt_number": 23
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#There is no TreeSet or similar collection in Python (can be done using normal list like 18.1) so skipping example 18.4"
],
"language": "python",
"metadata": {},
"outputs": [],
"prompt_number": 25
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 18.5, page no. 353"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\"\"\"\n",
"Note: there is no vector in Python. Doing using normal lists.\n",
"\"\"\"\n",
"\n",
"fruits = []\n",
"\n",
"fruits.append(\"Apple\")\n",
"fruits.append(\"Orange\")\n",
"fruits.append(\"Grapes\")\n",
"fruits.append(\"Pine\")\n",
"\n",
"for ele in fruits:\n",
" print ele"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Apple\n",
"Orange\n",
"Grapes\n",
"Pine\n"
]
}
],
"prompt_number": 26
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 18.6, page no. 354"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\"\"\"\n",
"In python we can use list itself as stack\n",
"\"\"\"\n",
"\n",
"st = []\n",
"\n",
"st.append(\"Java\")\n",
"st.append(\"latest\")\n",
"st.append(\"Edition\")\n",
"st.append(\"-fifth\")\n",
"\n",
"print \"The elements in the Stack: \", st\n",
"print \"The element at the top: \", st[-1:]\n",
"print \"The element poped out of the stack: \", st.pop()\n",
"print \"The element in a stack after pop out element: \", st\n",
"try:\n",
" \"The result of searching: \", st.index(\"r u\")\n",
"except ValueError:\n",
" print \"The result of searching: \", -1"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The elements in the Stack: ['Java', 'latest', 'Edition', '-fifth']\n",
"The element at the top: ['-fifth']\n",
"The element poped out of the stack: -fifth\n",
"The element in a stack after pop out element: ['Java', 'latest', 'Edition']\n",
"The result of searching: -1\n"
]
}
],
"prompt_number": 29
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 18.7, page no. 355"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\"\"\"\n",
"Note: we will use dictionaries\n",
"\"\"\"\n",
"\n",
"ht ={}\n",
"\n",
"ht['item1'] = \"Apple\"\n",
"ht['item2'] = \"Orange\"\n",
"ht['item3'] = \"Grapes\"\n",
"ht['item4'] = \"Pine\"\n",
"\n",
"for key in ht.iterkeys():\n",
" print ht[key]\n",
" "
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Orange\n",
"Grapes\n",
"Apple\n",
"Pine\n"
]
}
],
"prompt_number": 38
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 18.8, page no. 357"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"#Answers will differ due to difference in built-in techniques of the classes\n",
"\n",
"from random import shuffle\n",
"\n",
"l = []\n",
"\n",
"l.append(\"java\")\n",
"l.append(\"is\")\n",
"l.append(\"platform\")\n",
"l.append(\"independent\")\n",
"\n",
"l_r = list(reversed(l))\n",
"l_r = sorted(l_r)\n",
"\n",
"print \"List sorted in reverse order is: \"\n",
"for ele in l_r:\n",
" print ele,\n",
"\n",
"print \"\\nList shuffled: \"\n",
"shuffle(l_r)\n",
"for ele in l_r:\n",
" print ele,\n",
"\n",
"print \"\\nMinimum: \", min(l_r)\n",
"print \"Maximum: \", max(l_r)"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"List sorted in reverse order is: \n",
"independent is java platform \n",
"List shuffled: \n",
"java independent is platform \n",
"Minimum: independent\n",
"Maximum: platform\n"
]
}
],
"prompt_number": 2
}
],
"metadata": {}
}
]
}