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题目 Notice that the number 123456789 is a 9 digit number consisting exactly the numbers from 1 to 9, with no duplication. Double it we will obtain 2469 阅读全文
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题目 A Digital Library contains millions of books, stored according to their titles, authors, key words of their abstracts, publishers, and published ye 阅读全文
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题目 It is vitally important to have all the cities connected by highways in a war. If a city is occupied by the enemy, all the highways from/toward tha 阅读全文
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题目 A graph which is connected and acyclic can be considered a tree. The height of the tree depends on the selected root. Now you are supposed to find 阅读全文
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题目 Suppose that all the keys in a binary tree are distinct positive integers. Given the postorder and inorder traversal sequences, you are supposed to 阅读全文
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题目 A number that will be the same when it is written forwards or backwards is known as a Palindromic Number. For example, 1234321 is a palindromic num 阅读全文
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题目 There is a public bike service in Hangzhou City which provides great convenience to the tourists from all over the world. One may rent a bike at an 阅读全文
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题目 Suppose a bank has K windows open for service. There is a yellow line in front of the windows which devides the waiting area into two parts. All th 阅读全文
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题目 Suppose a bank has N windows open for service. There is a yellow line in front of the windows which devides the waiting area into two parts. The ru 阅读全文
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一、基本概念 二叉搜索树 （又叫二叉查找树、二叉排序树），具有以下特点： 1. 节点的左孩子的值小于节点本身； 2. 节点的右孩子的值大于节点本身； 3. 左右子树同样为二叉搜索树； 所以最终效果是: 节点左子树的所有节点的值都小于节点本身； 节点右子树的所有节点的值都大于节点本身； 对二叉搜素树的 阅读全文