JAVA PROG 6

Week-3:

a)    Write a Java program that checks whether a given string is a palindrome or not.

Program:

import java.io.*;

class Palindrome

{

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

        {

                int i,j;

                boolean flag=true;

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

                System.out.print("\nEnter String:");

                String s=br.readLine();

                j=s.length()-1;

                for(i=0;i<=j;i++)

                {

                    if(s.charAt(i)!=s.charAt(j--))

                                flag=false;

                }

                if(flag==false)         System.out.println("\n"+s+" Is Not Palindrome"); 

                else                          System.out.println("\n"+s+" Is Palindrome");

        }

}

Output:

Enter String: malayalam

malayalam Is Palindrome

JAVA PROGRAMS 5

a)    Write a Java Program that reads a line of integers, and then displays each integer, and the sum of all the integers (Use StringTokenizer class of java.util)

Program:

import java.io.*;

import java.util.*;

class SumOfInt

{

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

        {

                int sum=0;

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

                System.out.print("\nEnter String Of Integers:");

                String s=br.readLine();

                StringTokenizer st=new StringTokenizer(s,",");

                while(st.hasMoreTokens())

                {

                        int i=Integer.parseInt(st.nextToken());

                        sum=sum+i;

                        System.out.println(i);

                }

                System.out.println("\nSum Of Integers Is: "+sum);

        }

}

Output:

Enter String Of Integers:12,5,3,1,2

12

5

3

1

2

Sum Of Integers Is: 23

JAVA PROGRAMS 4

D)    Write a Java program to multiply two given matrices.

Program:

import java.io.*;

class MatrixMul

{

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

        {

                int r1,c1,r2,c2,i,j,k;

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

                System.out.print("Enter No. Of Rows & Columns for Matrix 1:");

                r1=Integer.parseInt(br.readLine());

                c1=Integer.parseInt(br.readLine());

                System.out.print("Enter No. Of Rows & Columns for Matrix 2:");

                r2=Integer.parseInt(br.readLine());

                c2=Integer.parseInt(br.readLine());

                if(r2==c1)

                {

                        int a[][]=new int[r1][c1];

                        int b[][]=new int[r2][c2];

                        int c[][]=new int[r1][c2];

                        System.out.println("Enter Values for Matrix 1:");

                        for(i=0;i<r1;i++)

                        {

                          for(j=0;j<c1;j++)

                                a[i][j]=Integer.parseInt(br.readLine());

                        }

                        System.out.println("Enter Values for Matrix 2:");

                        for(i=0;i<r2;i++)

                        {

                          for(j=0;j<c2;j++)

                                b[i][j]=Integer.parseInt(br.readLine());

                        }

                        System.out.println("MATRIX MULTIPLICATION RESULT:");

                        for(i=0;i<r1;i++)

                        {

                          for(j=0;j<c2;j++)

                          {

                                c[i][j]=0;

                                for(k=0;k<r2;k++)

                                       c[i][j]=(a[i][k]*b[k][j])+c[i][j];

                          }

                        }

                        for(i=0;i<r1;i++)

                        {

                          for(j=0;j<c2;j++)

                                System.out.print(" "+c[i][j]);

                          System.out.println();

                        }

                }

                else   System.out.print("Invalid ORDER Of Matrices");

       }

 }

Output:

Enter No. Of Rows & Columns for Matrix 1:2

3

Enter No. Of Rows & Columns for Matrix 2:3

2

Enter Values for Matrix 1:

1

2

3

4

5

6

Enter Values for Matrix 2:

1

2

3

4

5

6

MATRIX MULTIPLICATION RESULT:

 22  28

 49  64

JAVA PROGRAMS 3

C)    Write a Java program that prompts the user for an integer and then prints out all prime numbers up to that integer.

Program:

import java.io.*;

class Prime

{

         int i,j,count;

         void seq(int n)

         {

                System.out.print("The Prime Numbers Upto "+n+" Are: ");

                for(i=1;i<=n;i++)

                        {

                        count=0;

                        for(j=1;j<=i;j++)

                                    {

                                                if(i%j == 0)

                                                            count++;

                                    }

                                    if(count==2)

                                                System.out.print(" "+i);

                        }                               

         }

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

         {

           int n;

           Prime ob=new Prime();

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

           System.out.print("\nEnter The Value Of n: ");

           n=Integer.parseInt(br.readLine());

           ob.seq(n);

         }

}       

Output:

Enter The Value Of n: 21

The Prime Numbers Upto 21 Are: 2  3  5  7  11  13  17  19

JAVA PROGRAMS 2

B)      The Fibonacci sequence is defined by the following rule:

The first two values in the sequence are 1 and 1. Every subsequent value is the sum of the two values preceding it. Write a Java program that uses both recursive and non recursive functions to print the nth value in the Fibonacci sequence.

Program:

import java.io.*;

class Fibo

{

         int nonRecursive(int n1)

         {

                int f3=0,f1=0,f2=1;

                if(n1==0 || n1==1)        return n1;

                else

                {

                        int count=2;

                        while(count<=n1)

                        {

                                f3=f1+f2;

                                f1=f2;

                                f2=f3;

                                count++;

                        }

                        return f3;

                }

         }

         int recursive(int n1)

         {

                if(n1==0 || n1==1)               return n1;

                else                                      return recursive(n1-1)+recursive(n1-2);

         }

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

         {

           int n;

           Fibo ob=new Fibo();

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

           System.out.print("\nEnter The Value Of n: ");

           n=Integer.parseInt(br.readLine());

           System.out.println("RECURSIVE METHOD");

           System.out.println(+n+"th Value In Fibonacci Sequence Is:"+ob.recursive(n));

           System.out.println("\nNON RECURSIVE METHOD ");

           System.out.println(+n+"th Value In Fibonacci Sequence Is:"+ob.nonRecursive(n));

          }

}     

Output:

E:\Lab>java Fibo

Enter The Value Of n: 5

RECURSIVE METHOD

5th Value In Fibonacci Sequence Is:5

NON RECURSIVE METHOD

5th Value In Fibonacci Sequence Is:5