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Given a non-empty binary search tree and a target value, find the value in the BST that is closest to the target. Note: Given target value is a floati 阅读全文
摘要：
Given a string, determine if a permutation of the string could form a palindrome. For example,"code" -> False, "aab" -> True, "carerac" -> True. 要点：学习 阅读全文
摘要：
Design a logger system that receive stream of messages along with its timestamps, each message should be printed if and only if it is not printed in t 阅读全文