|A∪B∪C|=|A|+|B|+|C|-|A∩B|-|A∩C|-|B∩C|+|A∩B∩C| 这个是集合的容斥,交集差集什么的,这个在概率论经常用到吧 4008: The Leaf Eaters   Time Limit(Common/Java):5000MS/15000MS     Memory Limit:65536KByteTotal Submit: 61            Accepted:18 Description As we all know caterpillars love…

Description As we all know caterpillars love to eat leaves. Usually, a caterpillar sits on leaf, eats as much of it as it can (or wants), then stretches out to its full length to reach a new leaf with its front end, and finally "hops" to it by c…

Given a binary tree containing digits from 0-9 only, each root-to-leaf path could represent a number. An example is the root-to-leaf path 1->2->3 which represents the number 123. Find the total sum of all root-to-leaf numbers. For example, 1 / \ 2 3…

Autumn is a second spring when every leaf is a flower. 秋天即是第二个春天,每片叶子都是花朵.——阿尔贝·加缪…

TOJ 2776题目链接http://acm.tju.edu.cn/toj/showp2776.html 这题其实就是考虑的周全性...  贡献了好几次WA, 后来想了半天才知道哪里有遗漏.最大的问题就是, 当零头是13的时候, 不一定前面的光盘都刻录到最大值.比如29,16这种情况, 如果前面的刻录最大值,这样就需要3个盘,而最少的却是 2个就够了,(15,14) 即可:知道这种情况,这题基本就可以了: 注意一下这几个数据: 13 15 输出为2 29 16 输出为2 这条题目看起来很容易,但…

Sum Root to Leaf Numbers Given a binary tree containing digits from 0-9 only, each root-to-leaf path could represent a number. An example is the root-to-leaf path 1->2->3 which represents the number 123. Find the total sum of all root-to-leaf number…

zxa and leaf  Accepts: 25  Submissions: 249  Time Limit: 5000/2500 MS (Java/Others)  Memory Limit: 65536/65536 K (Java/Others) 问题描述 zxa有一棵含有nn个节点的无根树,包含(n-1)(n−1)条无向边,点从11到nn编号,定义每个点的度数为与这个点相连的边的数量,度数为11的节点被称作这棵树的叶子节点. zxa想给每个节点设置它的好看度,好看度必须为正整数.他的无根…

zxa and leaf Problem Description zxa have an unrooted tree with n nodes, including (n−1) undirected edges, whose nodes are numbered from 1 to n. The degree of each node is defined as the number of the edges connected to it, and each node whose degree…

Problem description: http://oj.leetcode.com/problems/sum-root-to-leaf-numbers/ Basic idea: To store the num vector in every node of tree by starting from leaf, the go up util to root. class Solution { public: vector<vector<int>> subNumbers(Tre…

# Definition for a binary tree node # class TreeNode: # def __init__(self, x): # self.val = x # self.left = None # self.right = None class Solution: # @param root, a tree node # @return an integer def sumNumbers(self, root): """ BFS the tre…