Java Code for Bubble sort

package My;

import java.util.Scanner;

class BubbleSort {
  public static void main(String []args) {
    int n, c, d, swap;
    Scanner in = new Scanner(System.in);

    System.out.println("Input number of integers to sort");
    n = in.nextInt();

    int array[] = new int[n];

    System.out.println("Enter " + n + " integers");

    for (c = 0; c < n; c++)
      array[c] = in.nextInt();

    for (c = 0; c < ( n - 1 ); c++) {
      for (d = 0; d < n - c - 1; d++) {
        if (array[d] > array[d+1]) /* For descending order use < */
        {
          swap       = array[d];
          array[d]   = array[d+1];
          array[d+1] = swap;
        }
      }
    }

    System.out.println("Sorted list of numbers");

    for (c = 0; c < n; c++)
      System.out.println(array[c]);
  }
}

Java program to print stars pattern

package My;

class stars {
  public static void main(String[] args) {
    int row, numberOfStars;

    for (row = 1; row <= 10; row++) {
      for(numberOfStars = 1; numberOfStars <= row; numberOfStars++) {
        System.out.print("*");
      }
      System.out.println(); // Go to next line
    }
  }
}

output :

*
**
***
****
*****

Java Program for Prime number

package My;

import java.util.*;

class PrimeNumbers
{

/*
*
* We have used sqrt method of Math package which find square root
* of a number. To check if an integer(say n) is prime you can check
*  if it is divisible by any integer from 2 to (n-1) or check from 2
*  to sqrt(n), first one is less efficient and will take more time.
*/
   public static void main(String args[])
   {
      int n, status = 1, num = 3;

      Scanner in = new Scanner(System.in);
      System.out.println("Enter the number of prime numbers you want");
      n = in.nextInt();

      if (n >= 1)
      {
         System.out.println("First "+n+" prime numbers are :-");
         System.out.println(2);
      }

      for ( int count = 2 ; count <=n ;  )
      {
         for ( int j = 2 ; j <= Math.sqrt(num) ; j++ )
         {
            if ( num%j == 0 )
            {
               status = 0;
               break;
            }
         }
         if ( status != 0 )
         {
            System.out.println(num);
            count++;
         }
         status = 1;
         num++;
      }        
   }
}

Java Program to find factorial

package My;

import java.util.Scanner;

class Factorial
{
   public static void main(String args[])
   {
      int n, c, fact = 1;

      System.out.println("Enter an integer to calculate it's factorial");
      Scanner in = new Scanner(System.in);

      n = in.nextInt();

      if ( n < 0 )
         System.out.println("Number should be non-negative.");
      else
      {
         for ( c = 1 ; c <= n ; c++ )
            fact = fact*c;

         System.out.println("Factorial of "+n+" is = "+fact);
      }
   }
}

Java program for binary search

package My;

import java.util.Scanner;

class BinarySearch
{
  public static void main(String args[])
  {
    int c, first, last, middle, n, search, array[];

    Scanner in = new Scanner(System.in);
    System.out.println("Enter number of elements");
    n = in.nextInt();
    array = new int[n];

    System.out.println("Enter " + n + " integers");


    for (c = 0; c < n; c++)
      array[c] = in.nextInt();

    System.out.println("Enter value to find");
    search = in.nextInt();

    first  = 0;
    last   = n - 1;
    middle = (first + last)/2;

    while( first <= last )
    {
      if ( array[middle] < search )
        first = middle + 1;  
      else if ( array[middle] == search )
      {
        System.out.println(search + " found at location " + (middle + 1) + ".");
        break;
      }
      else
         last = middle - 1;

      middle = (first + last)/2;
   }
   if ( first > last )
      System.out.println(search + " is not present in the list.\n");
  }
}

Java Program to Add two Matrix

package My;

import java.util.Scanner;

class AddTwoMatrix
{
   public static void main(String args[])
   {
      int m, n, c, d;
      Scanner in = new Scanner(System.in);

      System.out.println("Enter the number of rows and columns of matrix");
      m = in.nextInt();
      n  = in.nextInt();

      int first[][] = new int[m][n];
      int second[][] = new int[m][n];
      int sum[][] = new int[m][n];

      System.out.println("Enter the elements of first matrix");

      for (  c = 0 ; c < m ; c++ )
         for ( d = 0 ; d < n ; d++ )
            first[c][d] = in.nextInt();

      System.out.println("Enter the elements of second matrix");

      for ( c = 0 ; c < m ; c++ )
         for ( d = 0 ; d < n ; d++ )
            second[c][d] = in.nextInt();

      for ( c = 0 ; c < m ; c++ )
         for ( d = 0 ; d < n ; d++ )
             sum[c][d] = first[c][d] + second[c][d];  //replace '+' with '-' to subtract matrices

      System.out.println("Sum of entered matrices:-");

      for ( c = 0 ; c < m ; c++ )
      {
         for ( d = 0 ; d < n ; d++ )
            System.out.print(sum[c][d]+"\t");

         System.out.println();
      }
   }
}

Selenium Java Interview Questions

Add two matrix

Prime Number

Bubble Sort

Binary Search

Factorial