Best Time to Buy and Sell Stock
Given a list of daily stock prices, determine the maximum profit achievable by buying on one day and selling on a later day.
Minimum Window Substring
Implement a sliding window algorithm to find the minimum window substring containing all characters of a given pattern.
Reduce array to zero
Given an array of non-negative integers, each operation chooses two indices and subtracts 1 from each if both are positive. Return the minimum number of operations to reduce the array to all zeros, or -1 if impossible.
Minimum Size Subarray Sum
Given an array of positive integers, return the minimal length of a contiguous subarray with sum at least target, or 0 if none exists.
Minimum Window Subsequence
Given strings s and t, return the minimum window substring of s that contains t as a subsequence, or empty string if none exists.
Boats to Save People – Two Pointer
Implement a function that returns the minimum number of boats needed to rescue everyone, given a weight limit and each boat carrying at most two people.
Showing 1–6 of 6 challenges · 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.