Understanding Binary Search: A Powerful Algorithm for Efficient Searching
Efficiency is the most important factor when the search space is large. The less time we take to find the desired information, the more productive we can be. The binary search algorithm is one such algorithm that stands out in terms of efficiency. This article explores what binary search is and how it works.
TUTORIALALGORITHMSPROGRAMMINGCOMPUTER SCIENCEDATA STRUCTURES
Hiranmoy
1/20/20244 min read


Searching in a large data set is a crucial process where efficiency is a key metric.
There are several algorithms to do this, but the faster the process is the more is its popularity and importance.
Binary Search is one of the fastest and relevant searching algorithm that is apt when there is a large sorted data.
This article is all about Binary Search, we will deep dive into its core principle and also see some code examples.
What is Binary Search?
It is a process in which we find a particular element in a sorted list of data items, by comparing the search item with the item at the mid position.
The strategy is to check in which half of the data our search item might lie,
that is whether it falls in the left segment or the right one of the current mid value.
Please note that the data must be sorted, because the algorithm uses comparison of the search element with the middle data item in the data set.
By doing this we find in which half of the list the search item lies.
How Does Binary Search Work?
This algorithm works by iteratively breaking the total sorted data set in half until the element we are searching for is found or the search space is empty.
These are the steps:
Start the process with sorted search data.
Calculate the middle position of the data set ie, (upper index + lower index)/2, and find the data at that position
Now compare the middle element with the item to be searched, if it is equal print the position and break the loop.
If the search data is lesser than the middle value, provided that the data is sorted in ascending order, the search is done with the left segment - the values less than the middle element.
But if the search data is greater than the middle value, the search is continued with the right partition, as it will lie in the values greater than the middle data element.
Steps 2 to 5 will be repeated until the search item is found or the search data is reduced to an empty list.
In the process of slashing down the search space in half at each step,
the Binary Search algorithm truncates half of the remaining elements in each iteration.
This search process is much faster for large sets of data.
Check out this easiest explanation from my tutorial on Study Smart Innovations on how Binary Search Algorithm Works!
I create tutorials to help programming enthusiasts!
Time Complexity of Binary Search
If N is the total number of elements of the search data the time complexity of Binary Search will be O(log N).
This means if the size of the search data increases the time taken for this search increases logarithmically.
If we compute the complexity of Linear Search, it comes to be O(N) which will take more time than Binary Search Algorithm.
That is why Binary Search is better to use in case of large data sets.
Implementing Binary Search
Now that we understand how Binary Search works, let's take a look at a simple implementation in Python:
In this implementation, the function takes input an array (arr) and a target element (target) as input. It initializes two pointers, low and high, to keep track of the search space.
The function then enters a while loop that continues until the search space is empty.
Inside the loop, the function calculates the middle index (mid) of the search space and compares the middle element with the target element. If they are equal, the function returns the index of the target element.
If the middle element is less than the target element, the search continues in the right half of the array.
Otherwise, the search continues in the left half of the array.
If the target element is not found after the loop exits, the function returns -1 to indicate that the element is not present in the array.
Advantages of Binary Search
Binary Search offers several benefits over other searching algorithms:
Efficiency: The time complexity is O(log N), hence it is efficient for large datasets.
Applicability: Any sorted data sets be it an array, list, etc, can be used by this search algorithm. But please note that - the data needs to be sorted.
Flexibility: Different types of search criteria, such as finding the first occurrence of an element or finding the closest element to a given value can be easily handled by this search algorithm.
Limitations of Binary Search
Despite its advantages, Binary Search also has some drawbacks:
Sorted Dataset: Getting a sorted data set may not always be feasible but Binary Search requires the dataset to be sorted.
Memory Usage: As Binary Search requires random access to the dataset, it might not be efficient for all types of data structures for example: Linked Lists.
Insertion and Deletion: This search algorithm is not applicable in places where there are frequent insertions or deletions. It becomes hectic to sort every time after the update.
Conclusion
For sorted data sets binary search algorithm is best suited. It is very efficient in this case.
By cutting the data set into half each time, it slashes the search time making the process very fast.
Although there are limitations, Binary Search offers significant benefits in terms of efficiency and applicability.
Developers make informed decisions after knowing how Binary Search works. It aids them in implementing search functionality in their applications.
So the next time you find yourself searching for information in a large dataset, consider using Binary Search to save time and improve efficiency.