What Is Linear Search?
Linear search also referred to as sequential search is the simplest searching algorithm that searches for an element in a list in sequential order. It relies on the technique of traversing a list from start to end by exploring properties of all the elements that are found on the way. Linear sear is mostly very simple to implement and is practical when the list has only a few elements or when performing a single search in an un-ordered list (list which the items are not sorted).
Linear search is implemented using the following steps:
Step 1- Read the search element from the user
Step 2- Compare the search element with the first element in the list.
Step 3- If both are matched, then display ‘’given element is found’’ and terminate the function.
Step 4- if both are not matched, then compare search element with the next element in the list.
Step 5- Repeat steps 3 and 4 until search element is compared with last element in the list.
Step 6- if last element in the list also doesn’t match, then display ‘’Element is not found’’ and terminate the function.
What You Need To Know About Linear Search
- Linear search is an algorithm to find an element in a list by sequentially checking the elements of the list until finding the matching element.
- A linear search scans one item at a time without skipping to any item.
- Linear searches may be implemented on any linear container (vector, Single Linked list, double linked list).
- Linear search is easy to use because there is no need for any ordered elements.
- Linear search in C programming language does not require the sorted elements hence the elements are conveniently inserted at the bottom of the list.
- Linear search is repetitive or iterative as well as uses the sequential approach in its functionality.
- In linear search, performance is done by equality comparisons.
- In the linear search, worst case scenario for searching an element is equivalent to O(n) number of comparison. It occurs when the searching key is the last element.
- The best case scenario in a linear search is to find the element in the first position O(1). It occurs when the searching key is the first element.
- The time complexity of linear search happens to be O(n). Where n is the number of elements in the input range.
What Is Binary Search?
Binary search is an efficient algorithm for finding an item from a sorted list of items. It works by repeatedly dividing in half the portion of the list that could contain the item, until you have narrowed the possible locations to just one. One of the most common ways to use binary search is to find an item in a sorted array or list of large size. It’s time complexity makes it very fast as compared to other sorting algorithms.
Binary search algorithm works on the principle of divide and conquer. One of the major limitations of binary search is that the array or list of elements must be sorted for the algorithm to work on it.
Binary search looks for a particular item by comparing the middle most item of the collection. If a match occurs, then the index of item is returned. If the middle item is greater than the item, then the item is searched in the sub-array to the left of the middle item. Otherwise, the item is searched for in the sub-array to the right of the middle item. This process continues on the sub-array as well until the size of the sub-array reduces to zero.
What You Need To Know About Linear Search
- Binary search is an algorithm that finds the position of a target value within a sorted array.
- A binary search cuts down the search to half as soon as the middle of a sorted list is found.
- Binary searches can only be implemented on data structures where two-way traversal is possible. It is difficult to implement directly a binary search on a single linked list as we can’t traverse in both directions.
- The binary search is a bit complicated with elements being necessarily arranged in a given order.
- A binary search in C programming language requires sorted arrays for effective performance. This facilitates insertion of elements at their required place and in essence maintaining sorted lists.
- Binary search employs divide and conquer approach in its functionality. It divides the range into two-parts; left and right, and keeps finding recursively.
- In binary search, performance is done by ordering comparisons.
- In the binary search, the worst case scenario is O(Log_{2}n) number of similarities.
- The best case scenario is to find the element in the middle position O(1). It occurs when the searching key is in the middle of the sorted list.
- The time complexity of binary search is O(log_{2}n). Where n is the number of elements in the input range.
Also Read: Difference Between Binary Tree And Binary Search Tree
Difference Between Linear Search And Binary Search In Tabular Form
BASIS OF COMPARISON | LINEAR SEARCH | BINARY SEARCH |
Description | Linear search is an algorithm to find an element in a list by sequentially checking the elements of the list until finding the matching element. | Binary search is an algorithm that finds the position of a target value within a sorted array. |
How It Works | A linear search scans one item at a time without skipping to any item. | A binary search cuts down the search to half as soon as the middle of a sorted list is found. |
Implementation | Linear searches may be implemented on any linear container (vector, Single Linked list, double linked list). | Binary searches can only be implemented on data structures where two-way traversal is possible. |
Complexity | Linear search is easy to use because there is no need for any ordered elements. | The binary search is a bit complicated with elements being necessarily arranged in a given order. |
Sorted Elements | Linear search in C programming language does not require the sorted elements hence the elements are conveniently inserted at the bottom of the list. | A binary search in C programming language requires sorted arrays for effective performance. This facilitates insertion of elements at their required place and in essence maintaining sorted lists. |
Approach | Linear search is repetitive or iterative as well as uses the sequential approach in its functionality. | Binary search employs divide and conquer approach in its functionality. |
Performance | In linear search, performance is done by equality comparisons. | In binary search, performance is done by ordering comparisons. |
Worse-Case Scenario | In the linear search, worst case scenario for searching an element is equivalent to O(n) number of comparison. | In the binary search, the worst case scenario is O(Log_{2}n) number of similarities. |
Best-Case Scenario | The best case scenario in a linear search is to find the element in the first position O(1). | The best case scenario is to find the element in the middle position O(1). |
Time Complexity | The time complexity of linear search happens to be O(n). | The time complexity of binary search is O(log_{2}n). |