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Given three strings, return true if third string is interleaving of first and second string. By running some examples, it seems that as long as s1.len 阅读全文
摘要：
Given a matrix of 0s and 1s. Find biggest sub-square matrix entirely of 1s in this matrix. The same problem link is as follows. Maximal Square 阅读全文
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Given a binary search tree with the following tree node definition. next points to a node's inorder successor. Populate inorder successor for all node 阅读全文
摘要：
Given a binary tree, get all nodes that don't have sibling node, excluding the root node. Level order and pre order solutions. 阅读全文