{
"metadata": {
"name": ""
},
"nbformat": 3,
"nbformat_minor": 0,
"worksheets": [
{
"cells": [
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"example 6.1 page no : 188"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"#Note : python does not have reference variable.\n",
"\n",
"myScore = 1000;\n",
"mikesScore = myScore; #create a reference\n",
"print \"myScore is: \" , myScore\n",
"print \"mikesScore is: \" , mikesScore \n",
"print \"Adding 500 to myScore\\n\";\n",
"myScore += 500;\n",
"print \"myScore is: \" , myScore\n",
"print \"mikesScore is: \" , mikesScore\n",
"print \"Adding 500 to mikesScore\";\n",
"mikesScore += 500;\n",
"print \"myScore is: \" , myScore \n",
"print \"mikesScore is: \" , mikesScore"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"myScore is: 1000\n",
"mikesScore is: 1000\n",
"Adding 500 to myScore\n",
"\n",
"myScore is: 1500\n",
"mikesScore is: 1000\n",
"Adding 500 to mikesScore\n",
"myScore is: 1500\n",
"mikesScore is: 1500\n"
]
}
],
"prompt_number": 1
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"example 6.2 page no : 192"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"def badSwap(x,y):\n",
" x,y = y,x\n",
"\n",
"def goodSwap(x, y):\n",
" x[0],y[0] = y[0],x[0]\n",
"\n",
"myScore = [1500];\n",
"yourScore = [1000];\n",
"print \"Original values\";\n",
"print \"myScore: \" , myScore[0] \n",
"print \"yourScore: \" , yourScore[0]\n",
"print \"Calling badSwap()\\n\";\n",
"badSwap(myScore[0], yourScore[0]);\n",
"print \"myScore: \" , myScore[0] \n",
"print \"yourScore: \" , yourScore[0]\n",
"print \"Calling goodSwap()\\n\";\n",
"goodSwap(myScore, yourScore);\n",
"print \"myScore: \" , myScore[0] \n",
"print \"yourScore: \" , yourScore[0] ,"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Original values\n",
"myScore: 1500\n",
"yourScore: 1000\n",
"Calling badSwap()\n",
"\n",
"myScore: 1500\n",
"yourScore: 1000\n",
"Calling goodSwap()\n",
"\n",
"myScore: 1000\n",
"yourScore: 1500\n"
]
}
],
"prompt_number": 2
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"example 6.3 page no : 196"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"\n",
"def display(vec):\n",
" print \"Your items:\";\n",
" for i in vec:\n",
" print i\n",
"\n",
"inventory = []\n",
"inventory.append(\"sword\");\n",
"inventory.append(\"armor\");\n",
"inventory.append(\"shield\");\n",
"display(inventory);"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Your items:\n",
"sword\n",
"armor\n",
"shield\n"
]
}
],
"prompt_number": 3
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"example : 6.4 page no : 199"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"#returns a reference to a string\n",
"\n",
"def refToElement(vec,i):\n",
" return vec[i]\n",
"\n",
"inventory = []\n",
"inventory.append(\"sword\");\n",
"inventory.append(\"armor\");\n",
"inventory.append(\"shield\");\n",
"\n",
"#displays string that the returned reference refers to\n",
"print \"Sending the returned reference to cout:\"\n",
"print refToElement(inventory, 0) \n",
"#assigns one reference to another -- inexpensive assignment\n",
"print \"Assigning the returned reference to another reference.\";\n",
"rStr = refToElement(inventory, 1);\n",
"print \"Sending the new reference to cout:\";\n",
"print rStr\n",
"#copies a string object -- expensive assignment\n",
"print \"Assigning the returned reference to a string object.\";\n",
"s = refToElement(inventory, 2);\n",
"print \"Sending the new string object to cout:\";\n",
"print s\n",
"#altering the string object through a returned reference\n",
"print \"Altering an object through a returned reference.\";\n",
"rStr = \"Healing Potion\";\n",
"print \"Sending the altered object to cout:\";\n",
"print inventory[1] "
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Sending the returned reference to cout:\n",
"sword\n",
"Assigning the returned reference to another reference.\n",
"Sending the new reference to cout:\n",
"armor\n",
"Assigning the returned reference to a string object.\n",
"Sending the new string object to cout:\n",
"shield\n",
"Altering an object through a returned reference.\n",
"Sending the altered object to cout:\n",
"armor\n"
]
}
],
"prompt_number": 4
},
{
"cell_type": "heading",
"level": 3,
"metadata": {},
"source": [
"example 6.5 page no : 205"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"# global constants\n",
"X = 'X'\n",
"O = 'O'\n",
"EMPTY = ' ';\n",
"TIE = 'T';\n",
"NO_ONE = 'N';\n",
"\n",
"def instructions():\n",
" print \"Welcome to the ultimate man-machine showdown: Tic-Tac-Toe.\";\n",
" print \"--where human brain is pit against silicon processor\";\n",
" print \"Make your move known by entering a number, 0 - 8. The number\";\n",
" print \"corresponds to the desired board position, as illustrated:\";\n",
" print \"0 | 1 | 2\";\n",
" print \"---------\";\n",
" print \"3 | 4 | 5\\n\"; \n",
" print \"---------\";\n",
" print \"6 | 7 | 8\\n\\n\";\n",
" print \"Prepare yourself, human. The battle is about to begin.\";\n",
"\n",
"def askYesNo(question):\n",
" response =''\n",
" while (response != 'y' and response != 'n'):\n",
" print question , \" (y/n): \",\n",
" response = raw_input()\n",
" return response;\n",
"\n",
"def askNumber( question, high, low):\n",
" while True:\n",
" print question , \" (\" , low , \" - \" , high , \"): \",\n",
" number = int(raw_input())\n",
" if (number > high or number < low):\n",
" pass\n",
" else:\n",
" break\n",
" return number;\n",
"\n",
"def humanPiece():\n",
" global X,O,EMPTY,TIE,NO_ONE\n",
" go_first = askYesNo(\"Do you require the first move?\");\n",
" if (go_first == 'y'):\n",
" print \"Then take the first move. You will need it.\"\n",
" return X;\n",
" else:\n",
" print \"Your bravery will be your undoing. . . I will go first.\";\n",
" return O;\n",
"\n",
"def opponent( piece):\n",
" global X,O,EMPTY,TIE,NO_ONE\n",
" if (piece == X):\n",
" return O;\n",
" else:\n",
" return X;\n",
"\n",
"def displayBoard( board):\n",
" print \"\\n\\t\" , board[0] , \" | \" , board[1] , \" | \" , board[2];\n",
" print \"\\t\" , \"---------\";\n",
" print \"\\t\" , board[3] , \" | \" , board[4] , \" | \" , board[5];\n",
" print \"\\t\" , \"---------\";\n",
" print \"\\t\" , board[6] , \" | \" , board[7] , \" | \" , board[8];\n",
" print \"\\n\";\n",
"\n",
"def winner(board):\n",
" global X,O,EMPTY,TIE,NO_ONE\n",
" # all possible winning rows\n",
" WINNING_ROWS = [ [0,1,2],[3,4,5],[6,7,8],[0,3,6],[1,4,7],[2,5,8],[0,4,8],[2,4,6]]\n",
" TOTAL_ROWS = 8;\n",
" # if any winning row has three values that are the same (and not EMPTY),\n",
" # then we have a winner\n",
" for row in range (TOTAL_ROWS):\n",
" if ( (board[WINNING_ROWS[row][0]] != EMPTY) and\n",
" (board[WINNING_ROWS[row][0]] == board[WINNING_ROWS[row][1]]) and\n",
" (board[WINNING_ROWS[row][1]] == board[WINNING_ROWS[row][2]]) ):\n",
" return board[WINNING_ROWS[row][0]];\n",
" # since nobody has won, check for a tie (no empty squares left)\n",
" if EMPTY not in board:\n",
" return TIE;\n",
" return NO_ONE;\n",
"\n",
"def isLegal(move,board):\n",
" global X,O,EMPTY,TIE,NO_ONE\n",
" return (board[move] == EMPTY);\n",
"\n",
"def humanMove(board,human):\n",
" global X,O,EMPTY,TIE,NO_ONE\n",
" move = askNumber(\"Where will you move?\", len(board),0);\n",
" \n",
" while (not isLegal(move, board)):\n",
" print \"\\nThat square is already occupied, foolish human.\\n\";\n",
" move = askNumber(\"Where will you move?\", len(board),0);\n",
" \n",
" print \"Fine. . .\\n\";\n",
" return move;\n",
"\n",
"def computerMove(board, computer):\n",
" global X,O,EMPTY,TIE,NO_ONE\n",
" move = 0;\n",
" found = False;\n",
" #if computer can win on next move, that's the move to make\n",
" while (not found and move < len(board)):\n",
" if (isLegal(move, board)):\n",
" board[move] = computer;\n",
" found = winner(board) == computer;\n",
" board[move] = EMPTY;\n",
" if (not found):\n",
" move += 1\n",
" #otherwise, if human can win on next move, that's the move to make\n",
" if (not found):\n",
" move = 0;\n",
" human = opponent(computer);\n",
" while (not found and move < len(board)):\n",
" if (isLegal(move, board)):\n",
" board[move] = human;\n",
" found = winner(board) == human;\n",
" board[move] = EMPTY;\n",
" if (not found):\n",
" move += 1\n",
" #otherwise, moving to the best open square is the move to make\n",
" if (not found):\n",
" move = 0;\n",
" i = 0;\n",
" BEST_MOVES = [4, 0, 2, 6, 8, 1, 3, 5, 7] #pick best open square\n",
" while (not found and i < len(board)):\n",
" move = BEST_MOVES[i];\n",
" if (isLegal(move, board)):\n",
" found = True;\n",
" i += 1\n",
" print \"I shall take square number \" , move \n",
" return move;\n",
"\n",
"def announceWinner( winner, computer, human):\n",
" if (winner == computer):\n",
" print winner , \"'s won!\";\n",
" print \"As I predicted, human, I am triumphant once more -- proof\";\n",
" print \"that computers are superior to humans in all regards.\";\n",
" elif (winner == human):\n",
" print winner , \"'s won!\";\n",
" print \"No, no! It cannot be! Somehow you tricked me, human.\";\n",
" print \"But never again! I, the computer, so swear it!\";\n",
" else:\n",
" print \"It's a tie.\\n\";\n",
" print \"You were most lucky, human, and somehow managed to tie me.\\n\";\n",
" print \"Celebrate. . . for this is the best you will ever achieve.\\n\";\n",
"\n",
"\n",
"NUM_SQUARES = 9;\n",
"board = [EMPTY,EMPTY,EMPTY,EMPTY,EMPTY,EMPTY,EMPTY,EMPTY,EMPTY]\n",
"instructions();\n",
"human = humanPiece();\n",
"computer = opponent(human);\n",
"turn = X;\n",
"displayBoard(board);\n",
"while (winner(board) == NO_ONE):\n",
" if (turn == human):\n",
" move = humanMove(board, human);\n",
" board[move] = human;\n",
" else:\n",
" move = computerMove(board, computer);\n",
" board[move] = computer;\n",
" displayBoard(board);\n",
" turn = opponent(turn);\n",
"\n",
"announceWinner(winner(board), computer, human);\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
" Welcome to the ultimate man-machine showdown: Tic-Tac-Toe.\n",
"--where human brain is pit against silicon processor\n",
"Make your move known by entering a number, 0 - 8. The number\n",
"corresponds to the desired board position, as illustrated:\n",
"0 | 1 | 2\n",
"---------\n",
"3 | 4 | 5\n",
"\n",
"---------\n",
"6 | 7 | 8\n",
"\n",
"\n",
"Prepare yourself, human. The battle is about to begin.\n",
"Do you require the first move? (y/n): "
]
},
{
"name": "stdout",
"output_type": "stream",
"stream": "stdout",
"text": [
"y\n"
]
},
{
"output_type": "stream",
"stream": "stdout",
"text": [
" Then take the first move. You will need it.\n",
"\n",
"\t | | \n",
"\t---------\n",
"\t | | \n",
"\t---------\n",
"\t | | \n",
"\n",
"\n",
"Where will you move? ( 0 - 9 ): "
]
},
{
"name": "stdout",
"output_type": "stream",
"stream": "stdout",
"text": [
"0\n"
]
},
{
"output_type": "stream",
"stream": "stdout",
"text": [
" Fine. . .\n",
"\n",
"\n",
"\tX | | \n",
"\t---------\n",
"\t | | \n",
"\t---------\n",
"\t | | \n",
"\n",
"\n",
"I shall take square number 4\n",
"\n",
"\tX | | \n",
"\t---------\n",
"\t | O | \n",
"\t---------\n",
"\t | | \n",
"\n",
"\n",
"Where will you move? ( 0 - 9 ): "
]
},
{
"name": "stdout",
"output_type": "stream",
"stream": "stdout",
"text": [
"2\n"
]
},
{
"output_type": "stream",
"stream": "stdout",
"text": [
" Fine. . .\n",
"\n",
"\n",
"\tX | | X\n",
"\t---------\n",
"\t | O | \n",
"\t---------\n",
"\t | | \n",
"\n",
"\n",
"I shall take square number 1\n",
"\n",
"\tX | O | X\n",
"\t---------\n",
"\t | O | \n",
"\t---------\n",
"\t | | \n",
"\n",
"\n",
"Where will you move? ( 0 - 9 ): "
]
},
{
"name": "stdout",
"output_type": "stream",
"stream": "stdout",
"text": [
"7\n"
]
},
{
"output_type": "stream",
"stream": "stdout",
"text": [
" Fine. . .\n",
"\n",
"\n",
"\tX | O | X\n",
"\t---------\n",
"\t | O | \n",
"\t---------\n",
"\t | X | \n",
"\n",
"\n",
"I shall take square number 6\n",
"\n",
"\tX | O | X\n",
"\t---------\n",
"\t | O | \n",
"\t---------\n",
"\tO | X | \n",
"\n",
"\n",
"Where will you move? ( 0 - 9 ): "
]
},
{
"name": "stdout",
"output_type": "stream",
"stream": "stdout",
"text": [
"5\n"
]
},
{
"output_type": "stream",
"stream": "stdout",
"text": [
" Fine. . .\n",
"\n",
"\n",
"\tX | O | X\n",
"\t---------\n",
"\t | O | X\n",
"\t---------\n",
"\tO | X | \n",
"\n",
"\n",
"I shall take square number 8\n",
"\n",
"\tX | O | X\n",
"\t---------\n",
"\t | O | X\n",
"\t---------\n",
"\tO | X | O\n",
"\n",
"\n",
"Where will you move? ( 0 - 9 ): "
]
},
{
"name": "stdout",
"output_type": "stream",
"stream": "stdout",
"text": [
"3\n"
]
},
{
"output_type": "stream",
"stream": "stdout",
"text": [
" Fine. . .\n",
"\n",
"\n",
"\tX | O | X\n",
"\t---------\n",
"\tX | O | X\n",
"\t---------\n",
"\tO | X | O\n",
"\n",
"\n",
"It's a tie.\n",
"\n",
"You were most lucky, human, and somehow managed to tie me.\n",
"\n",
"Celebrate. . . for this is the best you will ever achieve.\n",
"\n"
]
}
],
"prompt_number": 2
}
],
"metadata": {}
}
]
}