65 lines
2.4 KiB
Markdown
65 lines
2.4 KiB
Markdown
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# Linear Search
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**linear search**, also known as **Sequential search** is a method for finding an element within a list. A linear search sequentially checks each element of the list until it finds an element that matches the target value. If the algorithm reaches the end of the list, the search terminates unsuccessfully.
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1. Time Complexity: O(n)
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2. Space Complexity: O(1)
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3. Applications: practical when the list has only a few elements when performing a single search in an unordered list.
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4. Founder's Name: Anatole Beck and Donald J. Newman (1970)
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Linear search is usually very **simple to implement**.
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## Steps/Algorithm:
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**Linear Search( Array A, Value x)**
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Step 1: Set i to 1
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Step 2: if i > n then go to step 7
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Step 3: if A[i] = x then go to step 6
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Step 4: Set i to i + 1
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Step 5: Go to Step 2
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Step 6: Print Element x Found at index i and go to step 8
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Step 7: Print element not found
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Step 8: Exit
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## Pseudocode
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**procedure linear_search (list, value)**
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```
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start procedure
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for each item in the list
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if match item == value
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return the item's location
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end if
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end for
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end procedure
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```
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## Example
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Input A[]: **10,20,30,40,50,60,70,80**
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Element to search: **50**
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Procedure:
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Step 1: i = 0
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Step 2: Comparing A[i] and Element to search, if equal numbers return i, else i = i + 1.
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**comparing 10 and 50 ->False**, i = i + 1
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Step 3: **comparing 20 and 50 ->False**, i = i + 1
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Step 4: **comparing 30 and 50 ->False**, i = i + 1
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Step 5: **comparing 40 and 50 ->False**, i = i + 1
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Step 6: **comparing 50 and 50 ->True -> Element Found**
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Output: i
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## Implementation
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- [C](https://github.com/MakeContributions/DSA/blob/main/algorithms/C/searching/linearsearch.c)
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- [C++](https://github.com/MakeContributions/DSA/blob/main/algorithms/CPlusPlus/Searching/linear-search.cpp)
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- [CSharp](https://github.com/MakeContributions/DSA/blob/main/algorithms/CSharp/src/Search/linear-search.cs)
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- [Go](https://github.com/MakeContributions/DSA/blob/main/algorithms/Go/searching/linear-search.go)
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- [Java](https://github.com/MakeContributions/DSA/blob/main/algorithms/Java/searching/linear-search.java)
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- [JavaScript](https://github.com/MakeContributions/DSA/blob/main/algorithms/JavaScript/src/searching/linear-search.js)
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- [Python](https://github.com/MakeContributions/DSA/blob/main/algorithms/Python/searching/linear_search.py)
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## Video URL
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[Watch Linear Search Implementation](https://www.youtube.com/watch?v=4GPdGsB3OSc)
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