Python List Indexing | Programming Tutorials

Introduction

In Python, a list is a collection of items that are ordered and changeable. Sometimes, we need to find all the indexes of a specific value in a list. In this challenge, you will create a function that returns a list of indexes of all the occurrences of an element in a list.

Skills Graph

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All Indexes of Value

Problem

Write a Python function called index_of_all(lst, value) that takes a list lst and a value value as arguments and returns a list of indexes of all the occurrences of value in lst.

To solve this problem, you can use enumerate() and a list comprehension to check each element for equality with value and adding i to the result.

Example

index_of_all([1, 2, 1, 4, 5, 1], 1) ## [0, 2, 5]
index_of_all([1, 2, 3, 4], 6) ## []

Summary

In this challenge, you learned how to find all the indexes of a specific value in a list using Python. You used enumerate() and a list comprehension to check each element for equality with value and adding i to the result. Keep practicing to improve your Python skills!

All Indexes of Value | Challenge