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Practice Arena

Python Coding
Challenges

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56 challenges 25 easy 23 medium 8 hard

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All Python Basics Strings & Text Lists & Arrays Dicts & Sets Functions & Closures OOP & Classes Data Structures & Algorithms Advanced Python

Python Basics medium

Fibonacci(n)

Return the nth Fibonacci number efficiently.

recursion dp memoization

Lists & Arrays medium

Flatten nested list

Yield every integer from an arbitrarily nested list, depth-first.

recursion generators

Data Structures & Algorithms medium

Quicksort

Implement quicksort and return a sorted list.

sorting recursion divide-and-conquer

Data Structures & Algorithms medium

Graph DFS

Return all nodes reachable from a start node via DFS.

graph DFS recursion

Showing 4 challenges · medium