binary search search code example

Example 1: binary search

import java.util.Scanner;

public class Binarysearch {

	public static void main(String[] args) {
		int[] x= {1,2,3,4,5,6,7,8,9,10,16,18,20,21};
		Scanner scan=new Scanner(System.in);
		System.out.println("enter the key:");
		int key=scan.nextInt();
		int flag=0;
		int low=0;
		int high=x.length-1;
		int mid=0;
		while(low<=high)
		{
			mid=(low+high)/2;
			if(key<x[mid])
			{
				high=mid-1;
			}
			else if(key>x[mid])
			{
				low=mid+1;
			}
			else if(key==x[mid])
			{
				flag++;
				System.out.println("found at index:"+mid);
				break;
			}
		}
		if(flag==0)
		{
			System.out.println("Not found");
		}
		

	}

}

Example 2: binary search

function binarySearchRicorsivo(array A, int p, int r, int v)
    if p > r
      return -1
     if v < A[p] or v > A[r]
       return -1
     q= (p+r)/2
     if A[q] == v
       return q
     else if A[q] > v
       return binarySearchRicorsivo(A,p,q-1,v)
     else