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A. A Complete Course in ISC Computer Science (Java) XI –XII

B. A Complete Course in CBSE Computer Science (C++) XI– XII

C. A Complete Course in ICSE Computer Applications (JAVA) IX—X

D. A Complete Course in ICSE Computer Science (C++) IX-X

 

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IMPORTANT QUESTIONS FOR ISC’ 2009 (XII)

 

PRACTICAL:

COMPUTER SCIENCE

PRACTICAL PAPER

Reading time : 15 mins

Planning session : 1 hr

Examination session:2 hrs

 

INSTRUCTIONS

  

1. Write an algorithm  for selected problem

2. Write a program and document your program using mnemonic  names and comments.

 

 

Test run the program on the computer using the given test data and get the print out in the format specified in the problem along with the program listing.

Choose any one question

Question 1.

Enter the text. Print the text  such that the words which have odd number of characters , change the case of  the characters which are present in the next word .

                 Input:      All that glitters is not gold.

                 Output:   all  that glitters is nOt gold.

 

                 Input:    They always talk  who never think.

Output: They always talk who Never think.

 

Input:   The empty vessels makes the  greatest  noise.

Output: thE  Empty vESSElS makEs ThE  grEatESt  noise.

 

 

Question 2.

                 Input  N elements in an array. Display its contents . you are required to perform the following task-

Print the frequency  of each number without repeating the duplicate ones.

Delete the numbers such that they exist only once.

Arrange the elements such that the largest goes to left , second largest to the right, third largest to the left again and so on

 

Input  dimension of the array : 10

Input elements of the array : 7  3  5 2  6 7  8  8  3 1

Frequency of  8: 2

Frequency of  7: 2

Frequency of  6: 1

Frequency of  5: 1

Frequency of  3: 2

Frequency of  2: 1

Frequency of 1: 1

 

Contents of array after deletion: 7  3  5  2  6  8  1

Sorted array :  7       5     2      1         3      6    8

 

 

Question 3.

 

Enter the elements in the array of the dimension N. (N should be an odd number).

You are required to –

1. Display contents of the array

Print the automorphic numbers of the matrix with the row number and column number. Find the square of the number. Extract the number of digits from the end which should be according to the number of digits present in entered number. If the number extracted and entered number are same then the number is automorphic.

Eg. Num:25,

Square:625

Eg num:6

Square :36

 

 

Print the row  elements which has maximum automorphic  numbers. If  the  rows have same frequency of   automorphics then print the row elements which has larger automorphic number.

 

Enter  N : 3

Elements of matrix :

3       5     82

76     23   384

32     8     6

Automorphic numbers :

Number                    row no.                                      column no.

5                                              1                                                                    2

76                                               2                                                                    1

384                                             2                                                                    3

6                                                 3                                                                    3

 

Row elements:   76   23   384

 

Enter N: 2

Elements of matrix :

889     2

4               25

 

Automorphic numbers:

Number         row no.     column no.

889                            1              1

25                              2                   2

 

Row elements :  889     2

 

ISC COMPUTER SCIENCE 2009 (GUESS PAPER)

Class XII Paper I  (Theory) (Three Hours)

Answer all questions in Part I (compulsory) and seven questions from Part II, choosing three questions from Section A and four questions from Section B.

All working, including rough work, should be done on the same sheet as the rest of the answer.

The intended marks for questions or parts of questions are given in brackets [ ].

PART I

Answer all questions.

While answering questions in this Part, indicate briefly your working and reasoning, wherever required.

 

Question 1.                                                                                                                                                [5X2=10]

 

(a)     Use the truth table to show that: (A . B + C )+ (A.B)’ =1                                              [ 2 ]

 (b)    State the two absorption laws. Verify  one of them using the truth table                          [ 2 ]

 (c)    Convert the given  function to its equivalent POS  form                                                     [ 2 ]                

          F(A,B,C) = S (0,2,3,4,6) 

 (d)   Convert the following function as a sum of minterms:                                                [ 2 ]

                 F(X, Y, Z) = X.Y + Y’.Z                                                                                                                               

 (e)   Simplify using laws of Boolean- (P+Q).(P’+Q’).(P’+Q) + P                                           [ 2 ]        

Question 2.                                                                                                                                                   [5X2=10]

(a) Define function overloading with an example.                                                                      [ 2 ]

 (b) What  are adders? Give its utility.                                                                                    [ 2 ]

 (c). Explain 3 input XNOR gate with the truth table.                                                                     [ 2 ]

 (d) Give an application of stack .                                                                                        [ 2 ]          

 (e) An array  A[-10…5, 2…8] is stored in the memory with each element requiring 4 bytes of storage. If the base address is  5000, determine the location of A[1][5] when the array is stored  row major wise.                                    [2]                              

Question 3.                                                                                                                                                [5X2=10]

         (a)    In the following, function someFn is a part of some class.                                             [5]

         void  somefn())

       {

for(int i=5;i<9;i++)

{       m=i;

         for(j=5;j>1;j-=2)

         m*=i +  j;

         r=i++ * j;

         cout<<m<<”  “<<”   “<<r<<endl;

}

cout<<i;

}

(b)  The following function is a part of the class Arrange which stores n integers in an array arr[ ]. The member function/ method bubbleSort( ) arranges the array in ascending order. There are five places in the code marked by ?1?, ?2?, ?3?, ?4?, ?5? that must be replaced by expressions or statements so that the program works correctly.

         void bubbleSort( ) {

         for (int i=0;i<n;i++)

      {

                  j=? 1 ?

                  while(j<? 2 ?i)                                      

                   {

                                             if(a[j]>?3?)

                                             {

                                             int val=arr[j];

                                             arr[j]=? 4 ?;

                                             arr[j+1]=val;

                                             }

                  ? 5 ?                  }                                       }

         (i) What is the expression or statement at ?1?                                                           [2]

         (ii) What is the expression or statement at ?2?                                                            [2]

         (iii) What is the expression or statement at ?3?                                                        [2]

         (iv) What is the expression or statement at ?4?                                                        [2]

         (v) What   is the expression  or statement at ?5?                                              [2]                                 

 

PART II   SECTION A Answer any three questions.

 

Question 4.                                                                                                                                [5X2=10]

         (a) Given the Boolean Function F(A,B,C,D) = S (0,1,2,8,10,11,12,13,14).

                  Use Karnaugh’s map to reduce this function F, using the given SOP form. Draw the logic gate diagram for the reduced SOP form. You may use gates with more than two inputs. Assume that variables and their complements are available as inputs.                                                                [5]

         (b) Now given D(A,B,C,D) = p (2, 3, 4, 5,6,7,8, 9, 12, 13).

Use Karnaugh’s map to reduce this function D using the given POS form. Draw the logic gate diagram for the reduced POS form. You may use gates with more that two inputs. Assume that variables and their complements are available as inputs.                                                                                                         [5]

Question 5.                                                                                                                                        [5X2=10]         

         The SOP expression for a combinational circuit that detects an error in the representation of a decimal digit in BCD is given as follows: E(A,B,C, D) = S (10, 11, 12, 13, 14, 15)

         (a) Use Karnaugh’s map to reduce this function E, using the given SOP form. Draw the logic gate diagram for the reduced SOP form. You may use gates with more than two inputs. Assume that variables and their complements are available as inputs.                                                                                                  [5]

         (b) Now implement E using the NAND gates only.

Show how it is equivalent to the original circuit.  You may use gates with more than two inputs. Assume that variables and their complements are available as inputs:                                                                     

Question 6.                                                                                                                [5X2=10]

(a) Draw the logic gate diagram of the given expression using NAND gate only.(A+B’).C                                                                                                      [2]    (b) What is meant by  MULTILEVEL INHERITANCE.                              [2]                          

       (c) What is a  Copy constructor.                                                                      [2]          

       (d) Define   decimal to binary Encoder.  Explain with  diagram                   [2X2]                                 Question  7.

         (a) What is a decoder? State any one of its applications.                                   [2]

         (b)      Draw the truth table and logic gate diagram for a 3 to 8 decoder circuit. Show the output at each stage.                     [6]

        (c) Find the complement of the expression using DeMorgans Law.

                  {A’ + (B’.C) } . ( A + B )

SECTION B

Answer any four questions. Each program should be written in such a way that it clearly depicts the logic of the problem. This can be achieved by using mnemonic names and comments in the program. (Flowcharts and Algorithms are not required).

Question  8.

Define the class sumseries with

Data members : int sum , num, X

Member functions – sumseries(int, int  )  initialize data members .

void print () – display sum

int factorial(int b) return factorial of b

int  power(int  c)  return X ^ c 

int  findsum(int n) – return sum of  the given series.  ( ^   stands for   power  and  ! for factorial )

1 -  X ^ 1 /  !2  +  X ^ 2 / !5  -  X ^ 3 /  ! 8   ……..  num terms.

Do not write the main function.

Question 9.

Class MyArray contains an array of dimension N X N where  (N<=100). The subscripts of the array elements vary from 0 to n-1. Some of the member functions/ methods of MyArray are given below:

Class name:                                                   MyArray

Data members/ instance variables:                     arr[][] - an array of  integers.

                                                                                     N- size of the array.

Member functions/ methods:

MyArray(int n, int  ar[][] )                                parameterized constructor to initialize N  and  arr.

void displayArray( )                                             displays  contents of array .

Myarray  sumMyarray ( Myarray  a1)        returns Myarray which is sum of  Myarray a1 and the current object

Also  write the main function.

Question 10.

You are given an array of  N integers.  A class  operation is defined with the following details .

class name :  operation

data members :  int  array[50]  to store maximum 50 elements.

                              int  S to store the size of array.

Member functions :

void   read ( )                                          to  accept the size of array and its  elements .

void  pritnarray()                                to display contents of the array

void putinnumber( int  n, int  p)     to insert element at  index p. Check the validity of p.

int takeout(int p)                                  delete element at p. Return -1 if p is invalid.

Do not write the main function

Question 11.

A set is a collection in which there is no duplication of elements. S = { 1, 6, 9, 24} is a set of 4 integer elements. An array of integers may be used to represent a set. You may assume that there will a maximum of 50 elements in the set. Following are some member functions of the class Set

Class name:                                              Set

Datamembers/ instance variables:

                                                                    arr- an  array  of  integers  to  store  the elements of the set.

                                                                    n an integer to store  the total number of elements in the set.

Member functions/ methods:

Set(int nn)                                                constructor to initialize n=nn and the array   arr

void readElements( )                              reads the elements of the set

void displayElements( )                         displays the elements of the set

int getSize( )                                            returns n, the number of elements in the set.

int has(int ele)                                        returns 1 if ele belongs to the current  set  object and 0 otherwise.

Set intersection(Set d)        returns the intersection of set object d and       the current set object i.e. the set containing the elements that are common to both the    sets.

Set unions (Set d)              returns the union of set object d and the current set object i.e. the set containing  the elements that are present in both the  sets. Specify the class Set giving the details of the functions int has(int ele), Set intersection(Set d), Set union(Set d).

You may assume that the other functions/ methods are written for you. You do not need to write the main function.

Question  12.

A  class String1 contains the text   and its derived class String2   performs various operations on string handling .

class name :                                                                               String1

Data Members                                                          char   text[]  maximum length 100 characters

                                                                                     int len  - length of the string

Member  functions                                                

String1()                                                                  default constructor

String1()                                                                   parameterized constructor

void display()                                                           to display text and its length

derived class name:                                                String2

Data  Members:                                                        vowels, spaces  for counting vowels and spaces

Member functions :

String2()                                                                   constructor

int countvowel()                                                      return no. of vowels

int   countspaces()                                                 return no. of spaces

void  reverse()                                                         to print each word of the text  from end.

                                                                                     Eg.  Sumit  and Amit  are good boys.

                                                                                     Output:  boys   good   are  Amit  and  Sumit.

void display()                                                        to print  the text,  reverse of the text, number of spaces and vowels

 

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Coding a Java Program USING JDK:

 

The Sun’s Java Development Kit (JDK) provides all the features to write programs. The JDK is available for systems running Windows NT and other versions accordingly.

 

To type a program, in WINDOWS, the Notepad or DOS editor is employed. A java program has two main parts - a class definition that encloses the entire program and a method called main that contains the body.

 

Once the program is typed in, it is saved as a file with an extension of Java. Usually, java files have the same name as their class definition.

 

This file is then compiled using javac. The javac program should be in the execution path for compilation of the Java code.

 

Once completed , a file by the same name, but with the class extension is created. This is the java bytecode file. 

 

The bytecode is then run using the Java interpreter. In the JDK, the java interpreter is called java.

 

To execute this, java followed by the file name without the class extension is typed at the DOS prompt. The above compilation and execution procedure works only if Sun’s Java compiler is used.

 

INPUT/OUTPUT METHODS OF JAVA

 

The readLine() method is the input statement of Java and println() method displays the output on the screen.

 

readLine():

 

The readLine() method or the function is invoked with the usage of an object of the class DataInputStream, and is  used to read the input from the keyboard as a string. This entered value is further converted into the corresponding required type using the data type wrapper classes.

 

Example Program :

 

// Example program to utilize readLine() method

import java.io.DataInputStream;

class p4

{

public static void main(String args[])

{

DataInputStream in = new DataInputStream(System.in);

int a=0;

int b=0;

try

{

System.out.println(“Enter the value of a”);

a=Integer.parseInt(in.readLine());

System.out.println(“Enter the value of b”);

b=Integer.parseInt(in.readLine());

System.out.println(“The sum of numbers is “+(a+b));

System.out.println(“The product of numbers is “+(a*b));

}

catch (Exception e)

{}

}

}

 

Output:

 

Enter the value of a

5

Enter the value of b

5

The sum of numbers is

10

The product of numbers is

25

 

In the above example program, the readLine() method is invoked with the inclusion of the class DataInputStream. The keywords try and catch is used to handle errors which may be encountered during the entry of the numbers using readLine() method.

Read ICSE Comp. Applications by S.Chand & Co.  for Details

 

 

EXAMPLE PROGRAM (INPUT BASED) FOR JAVA:

// Program to display the name of the week day as per the entered number

import java.io.*;    // import of all files

import java.lang.*;

class p4

    { public static void main(String args[]) throws IOException 

{ int num=0;

InputStreamReader in = new InputStreamReader(System.in);

BufferedReader input=new BufferedReader(in);

System.out.println(“Enter your choice:”);

num = Integer.parseInt(input.readLine()); 

// converting string to numeric

switch(num)

{case 1:System.out.println(“The day is Monday”); break;

case 2: System.out.println(“The day is Tuesday”); break;

 

 

 

case 3:System.out.println(“The day is Tuesday”);

break;

case 4:System.out.println(“The day is Wednesday”);

break;

case 5:System.out.println(“The day is Thursday”);

break;

case 6:System.out.println(“The day is Friday”);

break;

case 7:System.out.println(“The day is Saturday”);

break;

default:

System.out.println(num+”Sorry, this day of the week does not exist”);

 

}   }    }