BASICS OF PROGRAMMING ASSIGNMENT 1

Question 1a

Search for a name

Write a program to accept an array of names and a name and check whether the

name is present in the array. Return the count of occurrence. Use the following

array as input

{“Dave”, “Ann”, “George”, “Sam”, “Ted”, “Gag”, “Saj”, “Agati”, “Mary”, “Sam”,

“Ayan”, “Dev”, “Kity”, “Meery”, “Smith”, “Johnson”, “Bill”, “Williams”, “Jones”,

“Brown”, “Davis”, “Miller”, “Wilson”, “Moore”, “Taylor, “Anderson”, “Thomas”,

“Jackson”}

SOLUTION:

import java.io.*;

class program1

 {

 public static void main(String args[])

 {

 String[] names={“Dave”, “Ann”, “George”, “Sam”, “Ted”, “Gag”, “Saj”, “Agati”, “Mary”, “Sam”,“Ayan”, “Dev”, “Kity”, “Meery”, “Smith”, “Johnson”, “Bill”, “Williams”, “Jones”, “Brown”, “Davis”, “Miller”, “Wilson”, “Moore”, “Taylor, “Anderson”, “Thomas”,“Jackson”};

System.out.println("Enter a name to check");

InputStreamReader Inp=new InputStreamReader(System.in);

BufferedReader Br=new BufferedReader(Inp);

String name=Br.readLine();

 int count=0;

 for(int i=0;i<names.length;i++)

 {

 if(names[i].equals(name))

 count++;

 }

 if(count!=0)

 System.out.println("The Number of occurance of the Name is " + count );

 else

 System.out.println("Word not Found");

 }

 }

Output :

C:\Program Files\Java\jdk1.6.0_22\bin>javac program1.java

C:\Program Files\Java\jdk1.6.0_22\bin>java program1

 Enter a name to check

 Sam

The Number of occurance of the Name is 2

Question 1 b

Improve the understandability of the below given code:

The code below takes an array of 10 integer values as an argument,prints its values,increments it by 10 and again prints the incremented value

import java.util.*; 

        //importing the required packages

class problem3 

       //creating a class

{

int[] numArray = new int[10];

       // allocating memory to 10 integer elements in an array named 'numArray'

public static void incrementElements (int[] integerArray) 

      //defining the 'incrementElements()' method with one integer type array 'integerArray' as the parameter

{

int arraylen = integerArray.length;

      // initializing an integer variable 'arraylen' with the length, i.e. the no of elements in array

for (int i = 0; i < arraylen; i ++)

      //definition of 'for' loop to print the current values of array

{

System.out.println(integerArray[i]);

}

for (int i = 0; i < arraylen; i ++)

        //definition of 'for' loop to increment the current values of array

{

integerArray[i] = integerArray[i] + 10; //add 10 to each value of array

}

for (int i=0; i < arraylen; i ++)

      //definition of 'for' loop to print the updated values of array

{

System.out.println(integerArray[i]);

}

}  //class closes

Question 2a

Greatest common divisor                    

Calculate the greatest common divisor of two positive numbers a and b.

gcd(a,b) is recursively defined as

gcd(a,b) = a if a =b

gcd(a,b) = gcd(a-b, b) if a >b

gcd(a,b) = gcd(a, b-a) if b > a

Solution :

import java.io.*;

class findgcd

{ 

 int gcd(int a,int b)

 { 

            if(a==b)

             return a;

          else if(a>b)

           return(gcd(a-b,b));

           else

           return(gcd(a,b-a));

       }

  }

 class gcdtest1

  {

 public static void main(String arr[]) throws IOException

      {

        BufferedReader br=new BufferedReader(new InputStreamReader(System.in));

         System.out.println("Enter a::");

         int a=Integer.parseInt(br.readLine());

         System.out.println("Enter b::");

         int b=Integer.parseInt(br.readLine());

          findgcd g=new findgcd();

          System.out.println("Gcd of a and b is::"+g.gcd(a,b));

}

  }

Output:

C:\Program Files\Java\jdk1.6.0_22\bin>javac gcdtest1.java

C:\Program Files\Java\jdk1.6.0_22\bin>java gcdtest1

 Enter a::

 36

 Enter b::

 24

 Gcd of a and b is:: 12

Question 2b

Improve the understandability of the below given code:

The code explains BUBBLE SORT implentation.

class Problem1

     //creating a new class

{

int[] a; //declaring a new array 'a' of integer type to store the numbers

int nElems; //declaring an integer variable 'nElems' to hold no of elements in the array

public ArrayBub(int max) 

       //defining a new parameterised method to initialize the array with 'max' as size of the array

  {

   a = new int[max];

  }

public void insert(int value)  //defining  the insert method to insert values in the array

{

a[nElems] = value;  //assigning the value to array at current position

nElems++; //incrementing the position counter

}

public void Sort()   //defining the method to sort the array

{

int out, in;  // declaring two integer variables 'out' & 'in'

for(out=nElems-1; out>1; out--) //outer loop

for(in=0; in<out; in++) //inner loop

if( a[in] > a[in+1] ) //conditional statement to compare the adjacent values

swap(in, in+1); //swaping the two values by calling the 'swap()' function

}

public void swap(int one, int two)   //defining 'swap' function to perform swapping of elements

{

//interchanging the values

long temp = a[one];

a[one] = a[two];

a[two] = temp;

}

}

// class definition ends