03 2019 档案

python闭包
摘要：闭包 注意到返回的函数在其定义内部引用了局部变量args，所以，当一个函数返回了一个函数后，其内部的局部变量还被新函数引用，所以，闭包用起来简单，实现起来可不容易。 另一个需要注意的问题是，返回的函数并没有立刻执行，而是直到调用了f()才执行。我们来看一个例子： 在上面的例子中，每次循环，都创建了一 阅读全文
posted @ 2019-03-28 22:11 Archer-Fang 阅读(137) 评论(0) 推荐(0)
python 中的[:-1]和[::-1]
摘要：0、求回文数 回数是指从左向右读和从右向左读都是一样的数，例如12321，909。请利用filter()筛选出回数： # 测试: 1、案例解释 a='python'b=a[::-1]print(b) #nohtypc=a[::-2]print(c) #nhy#从后往前数的话，最后一个位置为-1d=a 阅读全文
posted @ 2019-03-28 21:45 Archer-Fang 阅读(609) 评论(0) 推荐(0)
Floyd算法-dp问题
摘要：求结点对之间有负数的距离。限制条件：不允许有包含负权值的边组成的回路。 例子： 1.初始化 其中distance矩阵表示i,j两结点之间的距离。 path矩阵，以第一行为例，表示0->0值为n表示不可达，0->1值为0表示可由0到1. 2.i,j两结点经过0结点的情况 以此类推。 代码： 阅读全文
posted @ 2019-03-23 16:55 Archer-Fang 阅读(259) 评论(0) 推荐(0)
最大子序列
摘要：Maximum subarray problem The maximum subarray problem is the task of finding the contiguous subarray within a one-dimensional array, a[1...n], of numb 阅读全文
posted @ 2019-03-19 13:30 Archer-Fang 阅读(176) 评论(0) 推荐(0)
整数拆分-dp问题
摘要：Integer Partition In number theory and combinatorics, a partition of a positive integer n, also called an integer partition, is a way of writing nas a 阅读全文
posted @ 2019-03-19 12:26 Archer-Fang 阅读(675) 评论(0) 推荐(0)
0-1背包问题-DP
摘要：中文理解： 0-1背包问题：有一个贼在偷窃一家商店时，发现有n件物品，第i件物品价值vi元，重wi磅，此处vi与wi都是整数。他希望带走的东西越值钱越好，但他的背包中至多只能装下W磅的东西，W为一整数。应该带走哪几样东西？这个问题之所以称为0-1背包，是因为每件物品或被带走；或被留下；小偷不能只带走 阅读全文
posted @ 2019-03-19 11:36 Archer-Fang 阅读(1291) 评论(0) 推荐(0)
最长递增子序列-dp问题
摘要：Longest Increasing Subsequence The longest increasing subsequence problem is to find a subsequence of a given sequence in which the subsequence's elem 阅读全文
posted @ 2019-03-19 10:59 Archer-Fang 阅读(177) 评论(0) 推荐(0)
编辑距离算法-DP问题
摘要：Levenshtein Distance The Levenshtein distance is a string metric for measuring the difference between two sequences. Informally, the Levenshtein dista 阅读全文
posted @ 2019-03-18 12:31 Archer-Fang 阅读(288) 评论(0) 推荐(0)
求最长公共子序列-DP问题
摘要：Longest common subsequence problem The longest common subsequence (LCS) problem is the problem of finding the longest subsequence common to all sequen 阅读全文
posted @ 2019-03-18 11:31 Archer-Fang 阅读(236) 评论(0) 推荐(0)
爬楼梯的动态规划问题
摘要：Staircase Problem There are n stairs, a person standing at the bottom wants to reach the top. The person can climb either 1 or 2 stairs at a time. Cou 阅读全文
posted @ 2019-03-18 11:04 Archer-Fang 阅读(212) 评论(0) 推荐(0)
雨水收集问题
摘要：Rain Terraces (Trapping Rain Water) Problem Given an array of non-negative integers representing terraces in an elevation map where the width of each 阅读全文
posted @ 2019-03-15 11:51 Archer-Fang 阅读(243) 评论(0) 推荐(0)
不同路径问题
摘要：Unique Paths Problem A robot is located at the top-left corner of a m x n grid (marked 'Start' in the diagram below). The robot can only move either d 阅读全文
posted @ 2019-03-15 10:58 Archer-Fang 阅读(188) 评论(0) 推荐(0)
斐波那契数列
摘要：斐波那契数列：0 1 1 2 3 5 8 13 21... 给出一个n，求数组。 代码如下： 阅读全文
posted @ 2019-03-15 10:42 Archer-Fang 阅读(117) 评论(0) 推荐(0)
跳跃问题
摘要：Jump Game The Problem Given an array of non-negative integers, you are initially positioned at the first index of the array. Each element in the array 阅读全文
posted @ 2019-03-14 13:51 Archer-Fang 阅读(316) 评论(0) 推荐(0)
图的DFS。。类似树的DFS
摘要：Depth-First Search (DFS) Depth-first search (DFS) is an algorithm for traversing or searching tree or graph data structures. One starts at the root (s 阅读全文
posted @ 2019-03-14 12:40 Archer-Fang 阅读(136) 评论(0) 推荐(0)
树的DFS
摘要：Depth-first search (DFS) is an algorithm for traversing or searching tree or graph data structures. One starts at the root (selecting some arbitrary n 阅读全文
posted @ 2019-03-14 11:32 Archer-Fang 阅读(145) 评论(0) 推荐(0)
归并算法实现
摘要：A recursive merge sort algorithm used to sort an array of 7 integer values. These are the steps a human would take to emulate merge sort (top-down). C 阅读全文
posted @ 2019-03-14 10:53 Archer-Fang 阅读(313) 评论(0) 推荐(0)
杨辉三角求特定的行中的各个数字
摘要：The rows of Pascal's triangle are conventionally enumerated starting with row n = 0 at the top (the 0th row). The entries in each row are numbered fro 阅读全文
posted @ 2019-03-11 13:59 Archer-Fang 阅读(668) 评论(0) 推荐(0)
汉诺塔问题
摘要：The Tower of Hanoi (also called the Tower of Brahma or Lucas' Tower and sometimes pluralized) is a mathematical game or puzzle. It consists of three r 阅读全文
posted @ 2019-03-11 13:11 Archer-Fang 阅读(267) 评论(0) 推荐(0)