Question

Write a JAVA program to search for an element in a given list of elements using binary search mechanism.

Answer 1

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");

  }

}