Python Coding
Challenges

Lists & Arrays hard

Sliding window maximum

Return the maximum of each window of size k as it slides across an array.

sliding-window deque arrays

+40 pts 35m

Functions & Closures hard

Curry a function

Auto-curry any multi-argument function so it returns partial applications until fully saturated.

functional closures inspect

+35 pts 30m

Data Structures & Algorithms hard

LRU cache decorator

Implement @lru_cache(maxsize=N) for unary functions using OrderedDict.

decorators caching OrderedDict

+50 pts 40m

Data Structures & Algorithms hard

Longest increasing subsequence

Return the length of the longest strictly increasing subsequence.

dp binary-search LIS

+45 pts 40m

Data Structures & Algorithms hard

Topological sort (Kahn)

Return a valid topological ordering of tasks, or [] if a cycle exists.

graph BFS topological-sort

+45 pts 40m

Data Structures & Algorithms hard

Word ladder length

Return the length of the shortest transformation from beginWord to endWord changing one letter at a time.

BFS graph strings

+45 pts 40m

Advanced Python hard

Data pipeline

Implement a Pipeline class supporting pipe chaining with the | operator.

functional OOP pipeline

+40 pts 35m

Advanced Python hard

Validated descriptor

Implement a TypedField descriptor that raises TypeError if the value is not of the expected type.

descriptors OOP metaclass

+40 pts 35m