摘要：
Check whether the original sequence org can be uniquely reconstructed from the sequences in seqs. The org sequence is a permutation of the integers fr 阅读全文
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There are a total of n courses you have to take, labeled from 0 to n - 1.Some courses may have prerequisites, for example to take course 0 you have to 阅读全文
摘要：
There are a total of n courses you have to take, labeled from 0 to n - 1. Some courses may have prerequisites, for example to take course 0 you have t 阅读全文
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Given an directed graph, a topological order of the graph nodes is defined as follow: For each directed edge A -> B in graph, A must before B in the o 阅读全文
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Given a undirected graph, a node and a target, return the nearest node to given node which value of it is target, return NULL if you can't find. There 阅读全文
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Clone an undirected graph. Each node in the graph contains a label and a list of its neighbors. How we serialize an undirected graph: Nodes are labele 阅读全文
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Given n nodes labeled from 0 to n - 1 and a list of undirected edges (each edge is a pair of nodes), write a function to check whether these edges mak 阅读全文
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Design an algorithm and write code to serialize and deserialize a binary tree. Writing the tree to a file is called 'serialization' and reading back f 阅读全文
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Given a binary tree, return the zigzag level order traversal of its nodes' values. (ie, from left to right, then right to left for the next level and 阅读全文
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Given a binary tree, design an algorithm which creates a linked list of all the nodes at each depth (e.g., if you have a tree with depth D, you'll hav 阅读全文