Hello everyone, welcome back to programminginpython.com! Here I am going to explain to you how to implement linear search algorithm in python. This linear search is a basic search algorithm which searches all the elements in the list and finds the required value. This is also known as sequential search.

Here in this technique, I compare each and every element with the key element to be found, if both of them matches, the algorithm returns that element is found and its position.

**You can also watch the video on YouTube here**

#### Code Visualization – Linear Search Algorithm

#### Time Complexity

Best Case |
O(1) |

Average Case |
O(n) |

Worst Case |
O(n) |

#### Algorithm

Given a list `L`

of `n`

elements with values or records,`L0 ... Ln-1`

and key/target element `K`

, linear search is used to find the index/position of the target `K`

in list `L`

- Initialize a boolean variable
`found`

and set it to False initially - Start for loop with
`i`

ranging from 0 to the length of the list - Check if key element is equal to
`L[i]`

- if equals
- set
`found`

boolean variable to`True`

- print the position of the element found
- break for loop

- set

- if equals
- If the boolean variable
`found`

is equal to`False`

after for loop, print that the element is not found in the list

#### Program

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__author__ = 'Avinash' lst = [] num = int(input("Enter size of list: \t")) for n in range(num): numbers = int(input("Enter any number: \t")) lst.append(numbers) x = int(input("\nEnter number to search: \t")) found = False for i in range(len(lst)): if lst[i] == x: found = True print("\n%d found at position %d" % (x, i)) break if not found: print("\n%d is not in list" % x) |

#### Output

#### Same algorithm in other programming languages

**In C language**: http://www.mycodingcorner.com/2015/01/c-linear-search.html

**In CPP language**: http://www.mycodingcorner.com/2015/03/cpp-program-for-implementing-linear-search-technique.html

**In Java language**: http://www.mycodingcorner.com/2015/01/java-linear-search.html