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Solution: Russian Doll Envelopes

Explore how to solve the Russian Doll Envelopes problem by sorting envelopes and applying binary search to find the longest increasing subsequence. Understand the importance of sorting widths ascending and heights descending, then use a binary search approach to optimize nesting calculations, achieving an efficient O(n log n) solution.

Statement

You are given a 2D array of integers, envelopes, where each element envelopes[i] = [wi, hi] represents the width and height of an envelope. An envelope can fit inside another if and only if its width and height are strictly smaller than the width and height of the other envelope. The task is to determine the maximum number of envelopes that can be nested inside each other, similar to Russian dollsRussian dolls, also known as stacking dolls or nesting dolls, are a set of wooden dolls of decreasing size placed one inside another. .

Constraints:

  • 11\leq envelopes.length 103\leq 10^3

  • envelopes[i].length ==2== 2

  • 11\leq ...