https://dmytros.blog/tags/detect-squares/ Recent content in Detect Squares on Dmytro's Blog https://dmytros.blog/images/papermod-cover.png https://dmytros.blog/images/papermod-cover.png Hugo en Tue, 23 Jun 2026 08:04:51 +0300 https://dmytros.blog/posts/leetcode-150-detect-squares/ Tue, 23 Jun 2026 08:04:51 +0300 https://dmytros.blog/posts/leetcode-150-detect-squares/ <h3 id="the-problem">The problem</h3> <p>You are given a stream of points on the X-Y plane. Design an algorithm that:</p> <ul> <li><strong>Adds</strong> new points from the stream into a data structure. <strong>Duplicate</strong> points are allowed and should be treated as different points.</li> <li>Given a query point, <strong>counts</strong> the number of ways to choose three points from the data structure such that the three points and the query point form an <strong>axis-aligned square</strong> with <strong>positive area</strong>.</li> </ul> <p>An <strong>axis-aligned square</strong> is a square whose edges are all the same length and are either parallel or perpendicular to the x-axis and y-axis.</p>