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925 challenges 556 easy 323 medium 46 hard

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Two Pointers & Sliding Window medium

Count Nice Subarrays

Given an array of integers, count the number of contiguous subarrays that contain exactly k odd numbers.

sliding-window two-pointers subarray

Two Pointers & Sliding Window medium

Closest Three Sum

Given an array of integers and a target, return the sum of three numbers that is closest to the target.

sorting two-pointers array

Two Pointers & Sliding Window medium

Count Nice Subarrays

Count subarrays that contain exactly k odd numbers.

sliding-window two-pointers counting

Showing 1–3 of 3 challenges · medium · Two Pointers & Sliding Window

Two Pointers & Sliding Window — Python coding challenges

What you will find here

This page lists two pointers & sliding window challenges — real Python problems you solve in the browser IDE with instant test feedback. Each challenge includes a clear brief, starter code, and automated checks.

Challenges vs tutorials and quizzes

Challenges test what you can build under constraints. For guided teaching, use our Python tutorials. For quick checks, try quizzes or copy snippets from code samples.