Java program for Binary Search

Program

package com.candidjava;

import java.util.Scanner;

public class BinarySearch
{

	public static void main(String args[])
	{
		int counter, num, item, array[], first, last, middle;
		Scanner input = new Scanner(System.in);
		System.out.println("Enter number of elements:");
		num = input.nextInt();

		array = new int[num];

		System.out.println("Enter " + num + " integers");
		for (counter = 0; counter < num; counter++)
			array[counter] = input.nextInt();

		System.out.println("Enter the search value:");
		item = input.nextInt();
		first = 0;
		last = num - 1;
		middle = (first + last) / 2;

		while (first <= last)
		{
			if (array[middle] < item)
				first = middle + 1;
			else if (array[middle] == item)
			{
				System.out.println(item + " found at location " + (middle + 1) + ".");
				break;
			}
			else
			{
				last = middle - 1;
			}
			middle = (first + last) / 2;
		}
		if (first > last)
			System.out.println(item + " is not found.\n");
	}
}

Output

Enter number of elements:

5

Enter 5 integers

1

4

7

9

14

Enter the search value:

7

7 found at location 3.

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