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Given a binary tree, find the leftmost value in the last row of the tree. Example 1: Example 2: Note: You may assume the tree (i.e., the given root no 阅读全文
摘要：
You have a number of envelopes with widths and heights given as a pair of integers (w, h). One envelope can fit into another if and only if both the w 阅读全文
摘要：
Given a 2D binary matrix filled with 0's and 1's, find the largest rectangle containing only 1's and return its area. For example, given the following 阅读全文