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Binary Search Algorithm

Binary Search also known as Algorithmic or binary chop is a searching algorithm that searches for a element in a sorted data structure. Binary search is a searching algorithm that searches the required value by comparing the target value with the middle value of the array.

The following is the algorithm for binary search implementation

Step 0 : Sort the array using any sorting algorithm (I am using bubble sort in the below program)
Step 1 : Initialize first = 0 and last  = list.size() - 1
Step 2 :  while first < last and the element is not found calculate mid = (first + last) / 2
Step 3 : Compare target value with middle element
Step 4 : if the middle value is greater than the target value then target value lies on the left side of the middle value do goto step 1 with last = mid - 1
Step 5 : if the middle value is lesser than the target value then target value lies on the right side of the middle value do goto step 1 with first = mid + 1
Step 6 : if middle value is equal to the target value return the position of the element as middle.
Step 7 : if first > last and element is not found then the element is not present in the array so display message stating element not found.
Step 8 : Stop.

Time complexity of binary search

Worst-case performanceO(log n)
Best-case performanceO(1)
Average performanceO(log n)
Worst-case space complexityO(1)

To know more about Binary Search click Here

The following is the implementation of Binary Search.

C Program

C++ Program

You might also be interested in 

Singly Linked List
Double Linked List
Linked List in Python
Infix to Prefix Conversion
Infix to Postfix Conversion
Binary Search Tree


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