DSA - Binary Search Algorithm

Hello Guys today i am going to show you Binary Search algorithm implementation in Javascript and Python.

Lets get started...

BINARY SEARCH -
Binary Search is searching technique which works on Divide and Conquer approach. It used to search any element in a sorted array.
As compared to linear, binary search is much faster with Time Complexity of O(logN) whereas linear search algorithm works in O(N) time complexity.

Input : arr[] = {1, 3, 5, 7, 8, 9}
x = 5
Output : Element found!

Input : arr[] = {1, 3, 5, 7, 8, 9}
x = 6
Output : Element not found!

JAVASCRIPT IMPLEMENTATION -

function BinarySearch(arr, x) {

    let start=0, end=arr.length-1;

    // Iterate while start not meets end
    while (start<=end){

        // Find the mid index
        let mid=Math.floor((start + end)/2);

        // If element is present at mid, return True
        if (arr[mid]===x){
        console.log(arr[mid]);
        return true;
        }

        // Else look in left or right half accordingly
        else if (arr[mid] < x)
             start = mid + 1;
        else
             end = mid - 1;
    }

    return false;
}

const arr = [1,0,90,899,6,4,67,343,901];
const result = BinarySearch(arr,10) ? 'Element found' : 'Element not found';
console.log(result);

OUTPUT -
343
Element found

PYTHON IMPLEMENTATION -

import math

def binarysearch(Arr,element):
  start = 0
  end = len(Arr) - 1

  while start <= end:
    mid = start + (end - start) // 2;
    if Arr[mid] == element:
      print(Arr[element])
      return True
    elif Arr[mid] < element:
      start = mid + 1
    else:
      end = mid - 1

  return -1

items = [1,2,3,4,5,6,7,8,9,10]
result ='Element found' if binarysearch(items,5) else 'Element not found' 

print(result)