摘要：1076 Forwards on Weibo Weibo is known as the Chinese version of Twitter. One user on Weibo may have many followers, and may follow many other users as 阅读全文

摘要：1034 Head of a Gang One way that the police finds the head of a gang is to check people's phone calls. If there is a phone call between A and B, we sa 阅读全文

摘要：1013 Battle Over Cities 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 hig 阅读全文

摘要：1021 Deepest Root 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 su 阅读全文

摘要：1022 Digital Library A Digital Library contains millions of books, stored according to their titles, authors, key words of their abstracts, publishers 阅读全文

摘要：1071 Speech Patterns People often have a preference among synonyms of the same word. For example, some may prefer "the police", while others may prefe 阅读全文

摘要：1100 Mars Numbers People on Mars count their numbers with base 13: Zero on Earth is called “tret” on Mars. The numbers 1 to 12 on Earch is called “jan 阅读全文

摘要：1060 Are They Equal If a machine can save only 3 significant digits, the float numbers 12300 and 12358.9 are considered equal since they are both save 阅读全文

摘要：1063 Set Similarity Given two sets of integers, the similarity of the sets is defined to be Nc/Nt*100%, where Nc is the number of distinct common numb 阅读全文

摘要：1047 Student List for Course Zhejiang University has 40,000 students and provides 2,500 courses. Now given the registered course list of each student, 阅读全文

摘要：1053 Path of Equal Weight 给定一个非空的树，树根为 RR。 树中每个节点 TiTi 的权重为 WiWi。 从 RR 到 LL 的路径权重定义为从根节点 RR 到任何叶节点 LL 的路径中包含的所有节点的权重之和。 现在给定一个加权树以及一个给定权重数字，请你找出树中所有的权 阅读全文

摘要：1004 Counting Leaves A family hierarchy is usually presented by a pedigree tree. Your job is to count those family members who have no child. Input Sp 阅读全文

摘要：1094 The Largest Generation A family hierarchy is usually presented by a pedigree tree where all the nodes on the same level belong to the same genera 阅读全文

摘要：1090 Highest Price in Supply Chain A supply chain is a network of retailers（零售商）, distributors（经销商）, and suppliers（供应商）-- everyone involved in moving 阅读全文

摘要：1079 Total Sales of Supply Chain A supply chain is a network of retailers（零售商）, distributors（经销商）, and suppliers（供应商）– everyone involved in moving a p 阅读全文

摘要：1102 Invert a Binary Tree The following is from Max Howell @twitter: Google: 90% of our engineers use the software you wrote (Homebrew), but you can’t 阅读全文

摘要：1086 Tree Traversals Again An inorder binary tree traversal can be implemented in a non-recursive way with a stack. For example, suppose that when a 6 阅读全文

摘要：1020 Tree Traversals Suppose that all the keys in a binary tree are distinct positive integers. Given the postorder and inorder traversal sequences, y 阅读全文

摘要：1098 Insertion or Heap Sort According to Wikipedia: Insertion sort iterates, consuming one input element each repetition, and growing a sorted output 阅读全文

摘要：1107 Social Clusters When register on a social network, you are always asked to specify your hobbies in order to find some potential friends with the 阅读全文