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"content": "<p>There are several squares being dropped onto the X-axis of a 2D plane.</p>\n\n<p>You are given a 2D integer array <code>positions</code> where <code>positions[i] = [left<sub>i</sub>, sideLength<sub>i</sub>]</code> represents the <code>i<sup>th</sup></code> square with a side length of <code>sideLength<sub>i</sub></code> that is dropped with its left edge aligned with X-coordinate <code>left<sub>i</sub></code>.</p>\n\n<p>Each square is dropped one at a time from a height above any landed squares. It then falls downward (negative Y direction) until it either lands <strong>on the top side of another square</strong> or <strong>on the X-axis</strong>. A square brushing the left/right side of another square does not count as landing on it. Once it lands, it freezes in place and cannot be moved.</p>\n\n<p>After each square is dropped, you must record the <strong>height of the current tallest stack of squares</strong>.</p>\n\n<p>Return <em>an integer array </em><code>ans</code><em> where </em><code>ans[i]</code><em> represents the height described above after dropping the </em><code>i<sup>th</sup></code><em> square</em>.</p>\n\n<p> </p>\n<p><strong>Example 1:</strong></p>\n<img alt=\"\" src=\"https://assets.leetcode.com/uploads/2021/04/28/fallingsq1-plane.jpg\" style=\"width: 500px; height: 505px;\" />\n<pre>\n<strong>Input:</strong> positions = [[1,2],[2,3],[6,1]]\n<strong>Output:</strong> [2,5,5]\n<strong>Explanation:</strong>\nAfter the first drop, the tallest stack is square 1 with a height of 2.\nAfter the second drop, the tallest stack is squares 1 and 2 with a height of 5.\nAfter the third drop, the tallest stack is still squares 1 and 2 with a height of 5.\nThus, we return an answer of [2, 5, 5].\n</pre>\n\n<p><strong>Example 2:</strong></p>\n\n<pre>\n<strong>Input:</strong> positions = [[100,100],[200,100]]\n<strong>Output:</strong> [100,100]\n<strong>Explanation:</strong>\nAfter the first drop, the tallest stack is square 1 with a height of 100.\nAfter the second drop, the tallest stack is either square 1 or square 2, both with heights of 100.\nThus, we return an answer of [100, 100].\nNote that square 2 only brushes the right side of square 1, which does not count as landing on it.\n</pre>\n\n<p> </p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>1 <= positions.length <= 1000</code></li>\n\t<li><code>1 <= left<sub>i</sub> <= 10<sup>8</sup></code></li>\n\t<li><code>1 <= sideLength<sub>i</sub> <= 10<sup>6</sup></code></li>\n</ul>\n",
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"If positions = [[10, 20], [20, 30]], this is the same as [[1, 2], [2, 3]]. Currently, the values of positions are very large. Can you generalize this approach so as to make the values in positions manageable?"
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