深搜和广搜是图很多算法的基础,很多图的算法都是从这两个算法中启发而来. 深搜简单地说就是直接一搜到底,然后再回溯,再一搜到底,一直如此循环到没有新的结点. 广搜简单地说就是一层一层的搜,像水的波纹一样往外面扩散,扩散到最外层搜索也就完成了. prim最小生成树.Dijkstra单源最短路径算法都使用了类似广度优先搜索的思想. 拓扑排序就可以用深搜来实现,分解强连通分量也可以用深搜来实现(转置图加两次深搜) 我们实现广搜时需要用队列来辅助我们进行.实现深搜时使用栈来辅助我们进行,所以显而易见的用递

这个题我看了,都是推荐的神马双向广搜,难道这个深搜你们都木有发现?还是特意留个机会给我装逼? Open the Lock Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 3014    Accepted Submission(s): 1323 Problem Description Now an emergent task for you

利用TreeView控件加载文件,必须遍历处所有的文件和文件夹. 深搜算法用到了递归. using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows

题目链接 https://acm.bnu.edu.cn/v3/problem_show.php?pid=52310 problem description Define the depth of a node in a rooted tree by applying the following rules recursively: • The depth of a root node is 0. • The depths of child nodes whose parents are with

题目链接 https://acm.bnu.edu.cn/v3/problem_show.php?pid=52305 problem  description In ICPCCamp, there are n cities and (n−1) (bidirectional) roads between cities. The i-th road is between the ai-th and bi-th cities. It is guaranteed that cities are conne

题目链接:HDU 5355 http://acm.split.hdu.edu.cn/showproblem.php?pid=5355 Problem Description There are m soda and today is their birthday. The 1-st soda has prepared n cakes with size 1,2,…,n. Now 1-st soda wants to divide the cakes into m parts so that th

POJ 2676 Sudoku Time Limit: 2000MS   Memory Limit: 65536K Total Submissions: 17627   Accepted: 8538   Special Judge Description Sudoku is a very simple task. A square table with 9 rows and 9 columns is divided to 9 smaller squares 3x3 as shown on the

codevs 1047 邮票面值设计 1999年NOIP全国联赛提高组  时间限制: 1 s  空间限制: 128000 KB  题目等级 : 钻石 Diamond 题目描述 Description 给定一个信封,最多只允许粘贴N张邮票,计算在给定K(N+K≤40)种邮票的情况下(假定所有的邮票数量都足够),如何设计邮票的面值,能得到最大值MAX,使在1-MAX之间的每一个邮资值都能得到. 例如,N=3,K=2,如果面值分别为1分.4分,则在1分-6分之间的每一个邮资值都能得到(当然还有8分.9

http://www.wikioi.com/problem/1049/ 这题我之前写没想到迭代加深,看了题解,然后学习了这种搜索(之前我写的某题也用过,,但是不懂专业名词 囧.) 迭代加深搜索就是限制搜索深度,一旦有可行解立即跳出,优化了深搜一直搜下去的毛病. (囧,这题搜索题写了我一下午,我搜索的确很弱啊!!!) 第一次写出来的版本我没有注意到,应该是从多个点拓展下去,而不是从某个点. 第二次写出来的版本的确从所有可行点拓展下去,但是样例都tle.. 第三次看了别人的标程发现直接向右和向拓展就

题目链接:poj1190 生日蛋糕 解题思路: 深搜,枚举:每一层可能的高度和半径 确定搜索范围:底层蛋糕的最大可能半径和最大可能高度 搜索顺序:从底层往上搭蛋糕,在同一层尝试时,半径和高度都是从大到小试 剪枝: ①已建好的面积已经超过目前求得的最优表面积,或者预见到搭完后面积一定会超过目前最优表面积,则停止搭建(最优性剪枝) ②预见到再往上搭,高度已经无法安排,或者半径无法安排,则停止搭建(可行性剪枝) ③还没搭的那些层的体积,一定会超过还缺的体积,则停止搭建(可行性剪枝) ④还没搭的那些层的

题目 //传说中的记忆化搜索,好吧,就是用深搜//多做题吧,,这个解法是搜来的,蛮好理解的 //题目大意:给出两堆牌,只能从最上和最下取,然后两个人轮流取,都按照自己最优的策略,//问说第一个人对多的分值.//解题思路:记忆化搜索,状态出来就非常水,dp[fl][fr][sl][sr][flag],//表示第一堆牌上边取到fl,下面取到fr,同样sl,sr为第二堆牌,flag为第几个人在取.//如果是第一个人,dp既要尽量大,如果是第二个人,那么肯定尽量小. http://www.2cto.co

[题目链接:HDOJ-2952] Counting Sheep Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 2476    Accepted Submission(s): 1621 Problem Description A while ago I had trouble sleeping. I used to lie awake,

http://poj.org/problem?id=3249 Test for Job Time Limit: 5000MS   Memory Limit: 65536K Total Submissions: 8206   Accepted: 1831 Description Mr.Dog was fired by his company. In order to support his family, he must find a new job as soon as possible. No

题目链接:http://acm.hdu.edu.cn/showproblem.php?pid=5648 题意:给定n,m(1<= n,m <= 15,000),求Σgcd(i|j,i&j);(1 <= i <= n,1<=j<=m); 至多三组数据,至多两组数据max(n,m) > 2000.至多一组数据max(n,m) > 8000; 很多题解是用递推打表,将数据压缩250倍,即[i][j]:代表[1...250*i][1...250*j],之后零

最小生成树计数 Description 现在给出了一个简单无向加权图.你不满足于求出这个图的最小生成树,而希望知道这个图中有多少个不同的最小生成树.(如果两颗最小生成树中至少有一条边不同,则这两个最小生成树就是不同的).由于不同的最小生成树 可能很多,所以你只需要输出方案数对31011的模就可以了. Input 第 一行包含两个数,n和m,其中1<=n<=100; 1<=m<=1000; 表示该无向图的节点数和边数.每个节点用1~n的整数编号.接下来的m行,每行包含两个整数:a,

描述 http://www.lydsy.com/JudgeOnline/problem.php?id=1615 一个主动轮带着一些轮子转,轮子带着轮子转,轮子带着轮子转...一个非主动轮只会被一个轮子带着转.求从主动轮到某一个轮子的路上所有轮子的转速的绝对值之和. 分析 从起点开始,枚举相接触的轮子,只要不是之前路上的(带着当前轮子转的)轮子,就继续往下走.宽搜深搜都可以. 注意: 1.%.0lf是会四舍五入的!所以要强制转化成int. 宽搜: #include <bits/stdc++.h>

Problem Description Angel was caught by the MOLIGPY! He was put in prison by Moligpy. The prison is described as a N * M (N, M <= 200) matrix. There are WALLs, ROADs, and GUARDs in the prison. Angel's friends want to save Angel. Their task is: approa

Problem Description === Op tech briefing, 2002/11/02 06:42 CST === "The item is locked in a Klein safe behind a painting in the second-floor library. Klein safes are extremely rare; most of them, along with Klein and his factory, were destroyed in Wo

1648: [Usaco2006 Dec]Cow Picnic 奶牛野餐 Time Limit: 5 Sec  Memory Limit: 64 MBSubmit: 554  Solved: 346[Submit][Status][Discuss] Description The cows are having a picnic! Each of Farmer John's K (1 <= K <= 100) cows is grazing in one of N (1 <= N <

题目链接: http://codeforces.com/problemset/problem/707/D 题目大意: 一个N*M的书架,支持4种操作 1.把(x,y)变为有书. 2.把(x,y)变为没书. 3.把x行上的所有书状态改变,有变没,没变有. 4.回到第K个操作时的状态. 求每一次操作后书架上总共多少书. 题目思路: [离线][深搜][树] 现场有思路不过没敢写哈.还是太弱了. 总共只用保存一张图,把操作看成一棵树,一开始I操作连接在I-1操作后,如果遇到操作4的话,把I操作与I-1操

Suppose that we have a square city with straight streets. A map of a city is a square board with n rows and n columns, each representing a street or a piece of wall. A blockhouse is a small castle that has four openings through which to shoot. The fo