Binary search for integer in array

The following example illustrates binary search of int in array.

import java.util.*;

class SearchInt

{

        public static void main(String args[])

        {

        Scanner s=new Scanner(System.in);

        System.out.println("Enter no.of elements");

        int n=s.nextInt();

        

        System.out.println("Enter elements into array");

        int[] a=new int[n];

        

  for(int i=0;i<n;i++)

  {

  a[i]=s.nextInt();

  }



 System.out.println("Enter search element");

        int sr=s.nextInt();



        Arrays.sort(a);

        

        System.out.println("Sorted array\n--------------");

    for(int k:a)

    System.out.println(k);



        int idx=Arrays.binarySearch(a,sr);

        

        System.out.println("Element found at (after sorting) "+idx);

        }

}

Sample Output

Enter no.of elements

8

Enter elements into array

6

9

8

7

5

6

45

45

Enter search element

8

Sorted array

--------------

5

6

6

7

8

9

45

45

Element found at (after sorting)  4

binarySearch(a,sr): Takes array and search element respectively. Static method of the class.

sort(a): a must be sorted before searching for proper results. Static method.

idx: The index (may be any index if repeated more than 1 time). index value is with respect to the sorted array and not to the original one.

Arrays: Located in the java.util package.