Removed duplicates

1 files changed, 1504 insertions, 0 deletions

diff --git a/ANSI_C_Programming_by_Yashwant_Kanetkar/.ipynb_checkpoints/chapter12-checkpoint.ipynb b/ANSI_C_Programming_by_Yashwant_Kanetkar/.ipynb_checkpoints/chapter12-checkpoint.ipynb
new file mode 100755
index 00000000..59c2b543
--- /dev/null
+++ b/ANSI_C_Programming_by_Yashwant_Kanetkar/.ipynb_checkpoints/chapter12-checkpoint.ipynb
@@ -0,0 +1,1504 @@
+{
+ "metadata": {
+  "name": "",
+  "signature": "sha256:a886cf212382fa732d2b3df088bbcba9a65ba4a31cbe899c80e912ac04c2747f"
+ },
+ "nbformat": 3,
+ "nbformat_minor": 0,
+ "worksheets": [
+  {
+   "cells": [
+    {
+     "cell_type": "heading",
+     "level": 1,
+     "metadata": {},
+     "source": [
+      "CHAPTER 12:FILE INPUT/OUTPUT"
+     ]
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "EXAMPLE ON PAGE:391"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      " \n",
+      "fp=open('PR1.txt','r')                              #open the file for reading\n",
+      "ch=fp.readlines()                                   #ch will store all content of file\n",
+      "print \"%s\" % (' '.join(ch))                         #prints content of file\n",
+      "print \"\\n\"\n",
+      "fp.close()"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "site:http://www.bzu.edu.pk/\n",
+        " user:siteuser@localhost\n",
+        " version:5.5.32-0ubuntu0.12.04.1\n",
+        " db: bzu\n",
+        " tables:\n",
+        " username:web,webadmin,webadministrator23\n",
+        " pass:71dc9f7af599450b23a3b5d54bc665c7,\t49fa1a081c8d5c8dcfa05d730803251a,\t*E8665C4049F515D836A3C8704D0543C6DA0FE96D\n",
+        "\n",
+        "\n"
+       ]
+      }
+     ],
+     "prompt_number": 8
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "EXAMPLE ON PAGE:394"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      " \n",
+      "try:\n",
+      "    fp=open('yoyo.txt','r')\n",
+      "    for line in fin:\n",
+      "        print line\n",
+      "    fp.close()\n",
+      "except:\n",
+      "    print 'cannot open file'"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "cannot open file\n"
+       ]
+      }
+     ],
+     "prompt_number": 9
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "EXAMPLE ON PAGE:395"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      " \n",
+      "nol=0\n",
+      "nom=0\n",
+      "nob=0\n",
+      "noc=0\n",
+      "fp=open('H4CK3R.txt','r')\n",
+      "while True:\n",
+      "    ch=fp.read(1)\n",
+      "    if not ch:\n",
+      "        break\n",
+      "    noc+=1\n",
+      "    if ch==' ':\n",
+      "        nob+=1\n",
+      "    if ch=='\\n':\n",
+      "        nol+=1\n",
+      "    if ch=='\\t':\n",
+      "        nom+=1\n",
+      "fp.close()\n",
+      "print \"\\n\"\n",
+      "fp.close()\n",
+      "print \"Number of characters=%d\\n\" % (noc)\n",
+      "print \"Number of blanks=%d\\n\" % (nob)\n",
+      "print \"Number of tabs=%d\\n\" % (nom)\n",
+      "print \"Number of lines=%d\\n\" % (nol)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "\n",
+        "\n",
+        "Number of characters=162\n",
+        "\n",
+        "Number of blanks=21\n",
+        "\n",
+        "Number of tabs=3\n",
+        "\n",
+        "Number of lines=4\n",
+        "\n"
+       ]
+      }
+     ],
+     "prompt_number": 10
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "EXAMPLE ON PAGE:396-397"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      " \n",
+      "import sys\n",
+      "try:\n",
+      "    fs=open('H4CK3R.txt','r')\n",
+      "except:\n",
+      "    print \"Cannot open file\"\n",
+      "    sys.exit(1)\n",
+      "try:\n",
+      "    ft=open('python.txt','w')\n",
+      "except:\n",
+      "    print \"Cannot open file\"\n",
+      "    fs.close()\n",
+      "    sys.exit(2)\n",
+      "ch=fs.readlines()\n",
+      "ft.writelines(ch)\n",
+      "fs.close()\n",
+      "ft.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[0;31mSystemExit\u001b[0m\u001b[0;31m:\u001b[0m 1\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Cannot open file\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stderr",
+       "text": [
+        "To exit: use 'exit', 'quit', or Ctrl-D.\n"
+       ]
+      }
+     ],
+     "prompt_number": 1
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "EXAMPLE ON PAGE:399"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      " \n",
+      "try:\n",
+      "    fp=open('POEM.txt','w')\n",
+      "except:\n",
+      "    print 'cannot open file'\n",
+      "print \"\\nEnter a few lines of text:\\n\"\n",
+      "s=' '\n",
+      "while (len(s)>0):\n",
+      "    s=raw_input()\n",
+      "    fp.writelines(s)\n",
+      "    fp.writelines(\"\\n\")\n",
+      "fp.close()"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "\n",
+        "Enter a few lines of text:\n",
+        "\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Shining and bright,they are forever,\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "so true about diamonds,\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "more so of memories,\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "especially yours!\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "\n"
+       ]
+      }
+     ],
+     "prompt_number": 15
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "EXAMPLE ON PAGE:400"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      " \n",
+      "try:\n",
+      "    fp=open('POEM.txt','r')\n",
+      "except:\n",
+      "    print 'cannot open file'\n",
+      "s=fp.read(99)\n",
+      "print \"%s\" % (s)\n",
+      "print \"\\n\"\n",
+      "fp.close()"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Shining and bright,they are forever,\n",
+        "so true about diamonds,\n",
+        "more so of memories,\n",
+        "especially yours!\n",
+        "\n",
+        "\n"
+       ]
+      }
+     ],
+     "prompt_number": 16
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "EXAMPLE ON PAGE:401-402"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      " \n",
+      "class emp():\n",
+      "    def __init__(self,**kwds):\n",
+      "        self.__dict__.update(kwds)\n",
+      "another='Y'\n",
+      "e=emp()\n",
+      "try:\n",
+      "    fp=open('EMPLOYEE.txt','w')\n",
+      "except:\n",
+      "    print 'cannot open file'\n",
+      "while another=='Y':\n",
+      "    print \"\\nEnter name,age and basic salary:\"\n",
+      "    e.name=raw_input()\n",
+      "    e.age=eval(raw_input())\n",
+      "    e.bs=eval(raw_input())\n",
+      "    ch=\"%s %d %f\" % (e.name,e.age,e.bs)\n",
+      "    fp.writelines(ch)\n",
+      "    fp.writelines(\"\\n\")\n",
+      "    print \"Add another record(Y/N)\"\n",
+      "    another=raw_input()\n",
+      "fp.close()"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "\n",
+        "Enter name,age and basic salary:\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Sunil\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "34\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "1250.50\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Add another record(Y/N)\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Y\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "\n",
+        "Enter name,age and basic salary:\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Sameer\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "21\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "1300.50\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Add another record(Y/N)\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Y\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "\n",
+        "Enter name,age and basic salary:\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Rahul\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "34\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "1400.55\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Add another record(Y/N)\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "n\n"
+       ]
+      }
+     ],
+     "prompt_number": 17
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "EXAMPLE ON PAGE:403-404"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      " \n",
+      "class emp():\n",
+      "    def __init__(self,**kwds):\n",
+      "        self.__dict__.update(kwds)\n",
+      "e=emp()\n",
+      "try:\n",
+      "    fp=open('EMPLOYEE.txt','r')                             # open the file for reading\n",
+      "except:\n",
+      "    print 'cannot open file'\n",
+      "for line in fp:                                                # iterate over each line\n",
+      "        e.name, e.age, e.bs = line.split()                     # split it by whitespace\n",
+      "        e.age = int(e.age)                                     # convert age from string to int\n",
+      "        e.bs = float(e.bs)                                     # convert bs from string to float\n",
+      "        print \"%s %d %f\\n\" %(e.name, e.age, e.bs)\n",
+      "fp.close()"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Sunil 34 1250.500000\n",
+        "\n",
+        "Sameer 21 1300.500000\n",
+        "\n",
+        "Rahul 34 1400.550000\n",
+        "\n"
+       ]
+      }
+     ],
+     "prompt_number": 18
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "EXAMPLE ON PAGE:404-405"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      " \n",
+      "import sys                                                 #for exit()\n",
+      "try:\n",
+      "    fs=open('H4CK3R.txt','rb')                             # open the file for reading\n",
+      "except:\n",
+      "    print 'cannot open file'\n",
+      "    sys.exit(1)\n",
+      "try:\n",
+      "    ft=open('python.txt','wb')                             # open the file for writing\n",
+      "except:\n",
+      "    print 'cannot open file'\n",
+      "    fs.close()\n",
+      "    sys.exit(2)\n",
+      "ch=fs.readlines()\n",
+      "ft.writelines(ch)\n",
+      "fs.close()\n",
+      "ft.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[0;31mSystemExit\u001b[0m\u001b[0;31m:\u001b[0m 1\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "cannot open file\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stderr",
+       "text": [
+        "To exit: use 'exit', 'quit', or Ctrl-D.\n"
+       ]
+      }
+     ],
+     "prompt_number": 2
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "EXAMPLE ON PAGE:407-408"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      " \n",
+      "class emp():\n",
+      "    def __init__(self,**kwds):\n",
+      "        self.__dict__.update(kwds)\n",
+      "another='Y'\n",
+      "e=emp()\n",
+      "try:\n",
+      "    fp=open('EMP.txt','wb')                             # open the file for reading\n",
+      "except:\n",
+      "    print 'cannot open file' \n",
+      "while another=='Y':\n",
+      "    print \"\\nEnter name,age and basic salary:\"\n",
+      "    e.name=raw_input()\n",
+      "    e.age=eval(raw_input())\n",
+      "    e.bs=eval(raw_input())\n",
+      "    ch=\"%s %d %f\" % (e.name,e.age,e.bs)\n",
+      "    fp.writelines(ch)\n",
+      "    print \"Add another record (Y/N)\"\n",
+      "    another=raw_input()\n",
+      "    if another=='Y':\n",
+      "        fp.writelines(\"\\n\")\n",
+      "fp.close()"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "\n",
+        "Enter name,age and basic salary:\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Suresh\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "24\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "1250.50\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Add another record (Y/N)\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Y\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "\n",
+        "Enter name,age and basic salary:\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Ranjan\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "21\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "1300.60\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Add another record (Y/N)\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Y\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "\n",
+        "Enter name,age and basic salary:\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Harish\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "28\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "1400.70\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Add another record (Y/N)\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "N\n"
+       ]
+      }
+     ],
+     "prompt_number": 21
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "EXAMPLE ON PAGE:409"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      " \n",
+      "class emp():\n",
+      "    def __init__(self,**kwds):\n",
+      "        self.__dict__.update(kwds)\n",
+      "e=emp()\n",
+      "try:\n",
+      "    fp=open('EMP.txt','rb')\n",
+      "except:\n",
+      "    print \"Cannot open file\"\n",
+      "for line in fp:\n",
+      "    e.name, e.age, e.bs = line.split()                     # split it by whitespace\n",
+      "    e.age = int(e.age)                                     # convert age from string to int\n",
+      "    e.bs = float(e.bs)                                     # convert bs from string to float\n",
+      "    print \"%s %d %f\\n\" %(e.name, e.age, e.bs)\n",
+      "fp.close()"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Suresh 24 1250.500000\n",
+        "\n",
+        "Ranjan 21 1300.600000\n",
+        "\n",
+        "Harish 28 1400.700000\n",
+        "\n"
+       ]
+      }
+     ],
+     "prompt_number": 22
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "EXAMPLE ON PAGE:411-414"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      " \n",
+      "class emp():\n",
+      "    def __init__(self,**kwds):\n",
+      "        self.__dict__.update(kwds)\n",
+      "e=emp()\n",
+      "try:\n",
+      "    fp=open('EMP.txt','rb+')                             # open the file for reading\n",
+      "except:\n",
+      "    try:\n",
+      "        fp=open('EMP.txt','wb+')                             # open the file for writing\n",
+      "    except:\n",
+      "        print 'cannot open file'\n",
+      "while 1:\n",
+      "    print \"1.Add Records\"\n",
+      "    print \"2.List Records\"\n",
+      "    print \"3.Modify Records\"\n",
+      "    print \"4.Delete Records\"\n",
+      "    print \"0.Exit\"\n",
+      "    print \"Your choice\"\n",
+      "    choice=eval(raw_input())\n",
+      "    def add():\n",
+      "        import os\n",
+      "        fp.seek(0,os.SEEK_END)\n",
+      "        another='Y'\n",
+      "        while another=='Y':\n",
+      "            print \"\\nEnter name,age and basic salary:\"\n",
+      "            e.name=raw_input()\n",
+      "            e.age=eval(raw_input())\n",
+      "            e.bs=eval(raw_input())\n",
+      "            ch=\"%s %d %f\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\" % (e.name,e.age,e.bs)\n",
+      "            fp.writelines(\"\\n\")\n",
+      "            fp.writelines(ch)\n",
+      "            print \"Add another record(Y/N)\"\n",
+      "            another=raw_input()\n",
+      "    def list():\n",
+      "        import os\n",
+      "        fp.seek(0,os.SEEK_SET)\n",
+      "        for line in fp:                             # iterate over each line\n",
+      "            if len(line)>10:\n",
+      "                e.name, e.age, e.bs = line.split()                     # split it by whitespace\n",
+      "                e.age = int(e.age)                                     # convert age from string to int\n",
+      "                e.bs = float(e.bs)                                     # convert bs from string to float\n",
+      "                print \"%s %d %f\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\" %(e.name, e.age, e.bs)\n",
+      "    def modify():\n",
+      "        another='Y'\n",
+      "        while another=='Y':\n",
+      "            print \"\\nEnter name of employee to modify\"\n",
+      "            empname=raw_input()\n",
+      "            import os\n",
+      "            fp.seek(0,os.SEEK_SET)\n",
+      "            for line in iter(fp.readline, ''):\n",
+      "                if len(line)>10:\n",
+      "                    e.name, e.age, e.bs=line.split()\n",
+      "                    e.age = int(e.age)                                     # convert age from string to int\n",
+      "                    e.bs = float(e.bs)\n",
+      "                    if(cmp(e.name,empname)==0):\n",
+      "                        c=len(line)\n",
+      "                        print \"\\nEnter new name,age & bs\"\n",
+      "                        e.name=raw_input()\n",
+      "                        e.age=eval(raw_input())\n",
+      "                        e.bs=eval(raw_input())\n",
+      "                        import os\n",
+      "                        fp.seek(-c,os.SEEK_CUR)\n",
+      "                        ch=\"%s %d %f\" % (e.name,e.age,e.bs)\n",
+      "                        fp.writelines(\"\\n\")\n",
+      "                        fp.writelines(ch)\n",
+      "                        fp.writelines(\"\\n\")\n",
+      "                        break\n",
+      "            print \"\\nModify another Record(Y/N)\"\n",
+      "            another=raw_input()\n",
+      "    def delete():\n",
+      "        another='Y'\n",
+      "        global fp\n",
+      "        while another=='Y':\n",
+      "            print \"\\nEnter name of employee to delete\"\n",
+      "            empname=raw_input()\n",
+      "            ft=open('TEMP.txt','wb')\n",
+      "            import os\n",
+      "            fp.seek(0,os.SEEK_SET)\n",
+      "            for line in fp:\n",
+      "                if len(line)>10:\n",
+      "                    e.name, e.age, e.bs=line.split()\n",
+      "                    e.age = int(e.age)                                     # convert age from string to int\n",
+      "                    e.bs = float(e.bs)\n",
+      "                    if(cmp(e.name,empname)!=0):\n",
+      "                        ch=\"%s %d %f\\t\\t\\t\\t\\t\\t\\t\\t\\t\\t\" % (e.name,e.age,e.bs)\n",
+      "                        ft.writelines(ch)\n",
+      "                        ft.writelines(\"\\n\")\n",
+      "            fp.close()\n",
+      "            ft.close()\n",
+      "            import os\n",
+      "            os.remove(\"EMP.txt\")                           # Delete file EMP.txt\n",
+      "            os.rename( \"TEMP.txt\", \"D:/EMP.txt\" )          # Rename a file from TEMP.txt to EMP.txt\n",
+      "            fp=open('EMP.txt','rb+')\n",
+      "            print \"Delete another record(Y/N)\"\n",
+      "            another=raw_input()\n",
+      "    def exit():\n",
+      "        import sys\n",
+      "        fp.close()\n",
+      "        sys.exit(0)\n",
+      "    def switch(c):\n",
+      "        return {1: add,\n",
+      "                2: list,\n",
+      "                3: modify,\n",
+      "                4: delete,\n",
+      "                0: exit,\n",
+      "                }[c]()\n",
+      "    switch(choice)"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "1.Add Records\n",
+        "2.List Records\n",
+        "3.Modify Records\n",
+        "4.Delete Records\n",
+        "0.Exit\n",
+        "Your choice\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "2\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Suresh 24 1250.500000\t\t\t\t\t\t\t\t\t\t\n",
+        "Ranjan 21 1300.600000\t\t\t\t\t\t\t\t\t\t\n",
+        "Harish 28 1400.700000\t\t\t\t\t\t\t\t\t\t\n",
+        "1.Add Records\n",
+        "2.List Records\n",
+        "3.Modify Records\n",
+        "4.Delete Records\n",
+        "0.Exit\n",
+        "Your choice\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "1\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "\n",
+        "Enter name,age and basic salary:\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Ram\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "20\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "5000\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Add another record(Y/N)\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Y\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "\n",
+        "Enter name,age and basic salary:\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "GOPAL\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "19\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "6755.5\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Add another record(Y/N)\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "N\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "1.Add Records\n",
+        "2.List Records\n",
+        "3.Modify Records\n",
+        "4.Delete Records\n",
+        "0.Exit\n",
+        "Your choice\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "2\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Suresh 24 1250.500000\t\t\t\t\t\t\t\t\t\t\n",
+        "Ranjan 21 1300.600000\t\t\t\t\t\t\t\t\t\t\n",
+        "Harish 28 1400.700000\t\t\t\t\t\t\t\t\t\t\n",
+        "Ram 20 5000.000000\t\t\t\t\t\t\t\t\t\t\n",
+        "GOPAL 19 6755.500000\t\t\t\t\t\t\t\t\t\t\n",
+        "1.Add Records\n",
+        "2.List Records\n",
+        "3.Modify Records\n",
+        "4.Delete Records\n",
+        "0.Exit\n",
+        "Your choice\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "3\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "\n",
+        "Enter name of employee to modify\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Ram\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "\n",
+        "Enter new name,age & bs\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Radhey\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "15\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "4687.66\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "\n",
+        "Modify another Record(Y/N)\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "N\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "1.Add Records\n",
+        "2.List Records\n",
+        "3.Modify Records\n",
+        "4.Delete Records\n",
+        "0.Exit\n",
+        "Your choice\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "2\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Suresh 24 1250.500000\t\t\t\t\t\t\t\t\t\t\n",
+        "Ranjan 21 1300.600000\t\t\t\t\t\t\t\t\t\t\n",
+        "Harish 28 1400.700000\t\t\t\t\t\t\t\t\t\t\n",
+        "Radhey 15 4687.660000\t\t\t\t\t\t\t\t\t\t\n",
+        "GOPAL 19 6755.500000\t\t\t\t\t\t\t\t\t\t\n",
+        "1.Add Records\n",
+        "2.List Records\n",
+        "3.Modify Records\n",
+        "4.Delete Records\n",
+        "0.Exit\n",
+        "Your choice\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "4\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "\n",
+        "Enter name of employee to delete\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Radhey\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Delete another record(Y/N)\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "N\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "1.Add Records\n",
+        "2.List Records\n",
+        "3.Modify Records\n",
+        "4.Delete Records\n",
+        "0.Exit\n",
+        "Your choice\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "2\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Suresh 24 1250.500000\t\t\t\t\t\t\t\t\t\t\n",
+        "Ranjan 21 1300.600000\t\t\t\t\t\t\t\t\t\t\n",
+        "Harish 28 1400.700000\t\t\t\t\t\t\t\t\t\t\n",
+        "GOPAL 19 6755.500000\t\t\t\t\t\t\t\t\t\t\n",
+        "1.Add Records\n",
+        "2.List Records\n",
+        "3.Modify Records\n",
+        "4.Delete Records\n",
+        "0.Exit\n",
+        "Your choice\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "4\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "\n",
+        "Enter name of employee to delete\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "GOPAL\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Delete another record(Y/N)\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "N\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "1.Add Records\n",
+        "2.List Records\n",
+        "3.Modify Records\n",
+        "4.Delete Records\n",
+        "0.Exit\n",
+        "Your choice\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "2\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Suresh 24 1250.500000\t\t\t\t\t\t\t\t\t\t\n",
+        "Ranjan 21 1300.600000\t\t\t\t\t\t\t\t\t\t\n",
+        "Harish 28 1400.700000\t\t\t\t\t\t\t\t\t\t\n",
+        "1.Add Records\n",
+        "2.List Records\n",
+        "3.Modify Records\n",
+        "4.Delete Records\n",
+        "0.Exit\n",
+        "Your choice\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "0\n"
+       ]
+      },
+      {
+       "ename": "SystemExit",
+       "evalue": "0",
+       "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 0\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stderr",
+       "text": [
+        "To exit: use 'exit', 'quit', or Ctrl-D.\n"
+       ]
+      }
+     ],
+     "prompt_number": 23
+    },
+    {
+     "cell_type": "heading",
+     "level": 2,
+     "metadata": {},
+     "source": [
+      "EXAMPLE ON PAGE:416-417"
+     ]
+    },
+    {
+     "cell_type": "code",
+     "collapsed": false,
+     "input": [
+      " \n",
+      "from StringIO import StringIO\n",
+      "buffer = StringIO()\n",
+      "print \"\\nEnter source file name\"\n",
+      "source=raw_input()\n",
+      "try:\n",
+      "    inhandle=open(source,'rb')\n",
+      "except:\n",
+      "    print \"Cannot open file\"\n",
+      "print \"Enter target file name\"\n",
+      "target=raw_input()\n",
+      "try:\n",
+      "    outhandle=open(target,'wb')\n",
+      "except:\n",
+      "    print \"Cannot open file\"\n",
+      "    inhandle.close()\n",
+      "bytes=inhandle.readlines()\n",
+      "buffer.write(bytes)\n",
+      "outhandle.writelines(buffer.getvalue())\n",
+      "buffer.close()\n",
+      "inhandle.close()\n",
+      "outhandle.close()"
+     ],
+     "language": "python",
+     "metadata": {},
+     "outputs": [
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "\n",
+        "Enter source file name\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "H4CK3R.txt\n"
+       ]
+      },
+      {
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "Enter target file name\n"
+       ]
+      },
+      {
+       "name": "stdout",
+       "output_type": "stream",
+       "stream": "stdout",
+       "text": [
+        "python.txt\n"
+       ]
+      }
+     ],
+     "prompt_number": 24
+    }
+   ],
+   "metadata": {}
+  }
+ ]
+}
\ No newline at end of file