Showing posts with label Binary Search. Show all posts
Showing posts with label Binary Search. Show all posts

Tuesday, May 27, 2014

Binary Search

import java.util.Arrays;
import java.util.Scanner;

public class BinarySearch{
    public static void main(String[] args){
        Scanner in = new Scanner(System.in);
        System.out.println("Enter the size of the array which should be greater than zero else it will throw InputMismatchException : ");
        int size = in.nextInt();
        int[] array = new int[size];
        System.out.println("Enter the elements of the array: ");
        for(int i=0; i<size; i++){   
            array[i] = in.nextInt();
        }
        System.out.println("Enter the search element: ");
        int s = in.nextInt();
       
        Arrays.sort(array); //binary search will work on sorted array only so sort first
        int first, last, middle;
        first=0;
        last = size-1;
        middle = (first+last)/2;
        int i=0;
        for(; i<size; i++){
            if(s>array[middle]){
                first = middle+1;
            }else if(s<array[middle]){
                last = middle-1;
            }else{
                printArray(array);
                System.out.println("Element "+s+" found in the array.");
                break;
            }
            middle= (first+last)/2;
        }
        if(i==size){
            printArray(array);
            System.out.println("Element "+s+" is not found in the array");
        }
    }
    public static void printArray(int[] a){
            System.out.println("Array of elements: ");
            System.out.print("{");
            for(int i:a){
                System.out.print(i+",");
            }
            System.out.println("}");
    }
}