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 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {},
     "source": [
      "Chapter 13: Simple pointers"
     ]
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 13.1, Page number: 225"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "# Variable declaration\n",
      "thing_var = 2\n",
      "\n",
      "# Calculation and result\n",
      "print ('Thing %d' % thing_var)\n",
      "\n",
      "thing_ptr = thing_var\n",
      "thing_ptr = 3\n",
      "print ('Thing %d' % thing_ptr)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Thing 2\n",
        "Thing 3\n"
       ]
      }
     ],
     "prompt_number": 1
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 13.2, Page number: 227"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "\n",
      "# Function declaration\n",
      "def inc_count (count_ptr) :\n",
      "   count_ptr += 1\n",
      "   return count_ptr\n",
      "\n",
      "# Calculation and result\n",
      "count = 0\n",
      "\n",
      "while (count < 10) :\n",
      "   print ('Count %d\\n' % inc_count (count))\n",
      "   count += 1"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Count 1\n",
        "\n",
        "Count 2\n",
        "\n",
        "Count 3\n",
        "\n",
        "Count 4\n",
        "\n",
        "Count 5\n",
        "\n",
        "Count 6\n",
        "\n",
        "Count 7\n",
        "\n",
        "Count 8\n",
        "\n",
        "Count 9\n",
        "\n",
        "Count 10\n",
        "\n"
       ]
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 13.3, Page number: 230"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "# Variable declaration\n",
      "array = ['0', '1', '2', '3', '4', '5', '6', '7', '8', '9']\n",
      "\n",
      "# Calculation and result\n",
      "print ('&array[index] (array+index) array[index]\\n')\n",
      "\n",
      "for index in range (0, 10) :\n",
      "   print ('0x%s 0x%s 0x%s\\n' % (id (array[index]), id (array[index]), array[index]))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "&array[index] (array+index) array[index]\n",
        "\n",
        "0x20916008 0x20916008 0x0\n",
        "\n",
        "0x20270280 0x20270280 0x1\n",
        "\n",
        "0x20733728 0x20733728 0x2\n",
        "\n",
        "0x20916464 0x20916464 0x3\n",
        "\n",
        "0x20270232 0x20270232 0x4\n",
        "\n",
        "0x20733560 0x20733560 0x5\n",
        "\n",
        "0x20270256 0x20270256 0x6\n",
        "\n",
        "0x20733752 0x20733752 0x7\n",
        "\n",
        "0x20916512 0x20916512 0x8\n",
        "\n",
        "0x20916032 0x20916032 0x9\n",
        "\n"
       ]
      }
     ],
     "prompt_number": 3
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 13.4, Page number: 232"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "# Variable declaration\n",
      "array = [4, 5, 8, 9, 8, 1, 0, 1, 9, 3]\n",
      "index = 0\n",
      "\n",
      "# Calculation and result\n",
      "while (array[index] != 0) :\n",
      "   index += 1\n",
      "\n",
      "print ('Number of elements before zero %d\\n' % index)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Number of elements before zero 6\n",
        "\n"
       ]
      }
     ],
     "prompt_number": 4
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 13.5, Page number: 232"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "# Variable declaration\n",
      "array = [4, 5, 8, 9, 8, 1, 0, 1, 9, 3]\n",
      "index = 0\n",
      "\n",
      "# Calculation and result\n",
      "while (array[index] != 0) :\n",
      "   index += 1\n",
      "\n",
      "print ('Number of elements before zero %d\\n' % index)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Number of elements before zero 6\n",
        "\n"
       ]
      }
     ],
     "prompt_number": 5
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 13.6, Page number: 233"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "# Variable declaration\n",
      "data = []\n",
      "\n",
      "# Calculation and result\n",
      "for index in range (0, 10) :\n",
      "   data.append(0)\n",
      "print (data)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "[0, 0, 0, 0, 0, 0, 0, 0, 0, 0]\n"
       ]
      }
     ],
     "prompt_number": 6
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 13.10, Page number: 238"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "\n",
      "# Variable declaration\n",
      "line = 'Steve/Oualline'\n",
      "\n",
      "# Calculation and result\n",
      "first_ptr, last_ptr = line.split('/')\n",
      "print ('First: %s Last: %s\\n' % (first_ptr, last_ptr))"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "First: Steve Last: Oualline\n",
        "\n"
       ]
      }
     ],
     "prompt_number": 8
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 13.11, Page number: 240"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "# Function declaration\n",
      "def tmp_name() :\n",
      "   if not hasattr (tmp_name, 'sequence') :\n",
      "      tmp_name.sequence = 0\n",
      "   tmp_name.sequence += 1\n",
      "   name = 'tmp'\n",
      "   name += str (tmp_name.sequence)\n",
      "   return name\n",
      "\n",
      "# Calculation and result\n",
      "print ('Name: %s\\n' % tmp_name())"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Name: tmp1\n",
        "\n"
       ]
      }
     ],
     "prompt_number": 9
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 13.12, Page number: 245"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "\n",
      "# Variable and function declaration\n",
      "import sys\n",
      "v_count = sys.argv\n",
      "counter = len(sys.argv)\n",
      "\n",
      "# Produces verbose messages\n",
      "verbose = 0\n",
      "\n",
      "# Sends output to a file\n",
      "out_file = open ('print.out', 'w')\n",
      "\n",
      "# Sets the number of lines per page\n",
      "line_max = 66\n",
      "\n",
      "def do_file (name) :\n",
      "   print ('Verbose %d Lines %d Input %s Output %s\\n' % (verbose, line_max, name, out_file.name))\n",
      "\n",
      "def usage() :\n",
      "   print ('Usage is %s [options] [file-list]\\n' % program_name)\n",
      "   print ('Options\\n')\n",
      "   print (' -v verbose\\n')\n",
      "   print (' -l<number> Number of lines\\n')\n",
      "   print (' -o<name> Set output filename\\n')\n",
      "   sys.exit(1)\n",
      "   \n",
      "# Calculation and result\n",
      "program_name = str (sys.argv[0])\n",
      "\n",
      "while ((counter > 1) and (sys.argv[1][0] == '-')) :\n",
      "   if (sys.argv[1][1] == 'v') :\n",
      "      verbose = 1\n",
      "      break\n",
      "\n",
      "   elif (sys.argv[1][1] == 'o') :\n",
      "      temp = str (sys.argv[1])\n",
      "      out_file.write (temp)\n",
      "      break\n",
      "\n",
      "   elif (sys.argv[1][1] == 'l') :\n",
      "      line_max = int (sys.argv[1][2])\n",
      "      break\n",
      "\n",
      "   else :\n",
      "      print ('Bad option %s\\n' % sys.argv[1])\n",
      "      usage()\n",
      "\n",
      "   for index in range (0, counter) :\n",
      "      if (index == counter - 1) :\n",
      "         break\n",
      "      else :\n",
      "         v_count[index] = v_count[index + 1]\n",
      "\n",
      "   counter -= 1\n",
      "\n",
      "if (counter == 1) :\n",
      "   do_file ('print.in')\n",
      "\n",
      "else :\n",
      "   while (counter > 1) :\n",
      "      do_file (sys.argv[1])\n",
      "\n",
      "      for index in range (0, counter) :\n",
      "         if (index == counter - 1) :\n",
      "            break\n",
      "         else :\n",
      "            v_count[index] = v_count[index + 1]\n",
      "         \n",
      "      counter -= 1\n",
      "\n",
      "out_file.close()"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "ename": "SystemExit",
       "evalue": "1",
       "output_type": "pyerr",
       "traceback": [
        "An exception has occurred, use %tb to see the full traceback.\n",
        "\u001b[1;31mSystemExit\u001b[0m\u001b[1;31m:\u001b[0m 1\n"
       ]
      },
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Bad option -f\n",
        "\n",
        "Usage is -c [options] [file-list]\n",
        "\n",
        "Options\n",
        "\n",
        " -v verbose\n",
        "\n",
        " -l<number> Number of lines\n",
        "\n",
        " -o<name> Set output filename\n",
        "\n"
       ]
      },
      {
       "output_type": "stream",
       "stream": "stderr",
       "text": [
        "To exit: use 'exit', 'quit', or Ctrl-D."
       ]
      }
     ],
     "prompt_number": 10
    },
    {
     "cell_type": "heading",
     "level": 3,
     "metadata": {},
     "source": [
      "Example 13.13, Page number: 248"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "\n",
      "\n",
      "# Function declaration\n",
      "def tmp_name() :\n",
      "   if not hasattr (tmp_name, 'sequence') :\n",
      "      tmp_name.sequence = 0\n",
      "   tmp_name.sequence += 1\n",
      "   name = 'tmp'\n",
      "   name += str (tmp_name.sequence)\n",
      "   return name\n",
      "\n",
      "# Calculation and result\n",
      "name1 = tmp_name()\n",
      "name2 = tmp_name()\n",
      "print ('Name1: %s\\n' % name1)\n",
      "print ('Name2: %s\\n' % name2)"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Name1: tmp1\n",
        "\n",
        "Name2: tmp2\n",
        "\n"
       ]
      }
     ],
     "prompt_number": 11
    }
   ],
   "metadata": {}
  }
 ]
}