题目描述:有一个大小为N*M的园子,八连通的积水被认为是连接在一起的.请求出园子里总共有多少水洼?(八连通指的是下图中相对w的*部分) *** *w* *** 限制条件 N,M<=100 样例 输入: N=10,M=12 园子如下图('w'表示积水,'.'表示没有积水) w . . . . . . . . ww . . www . . . . www . . . . ww . . . ww . . . . . . . . . . . ww . . . . . . . . . . . w . .…

题目链接POJ NO.2386 解题思路: 这个也是一个dfs 的应用,在书上的例子,因为书上的代码并不全,基本都是函数分块来写,通过这个题目也规范了代码,以后能用函数的就都用函数来实现吧.采用深度优先搜索,从任意的w开始,不断把邻接的部分用'.'代替,1次DFS后与初始这个w连接的所有w就全都被替换成'.',因此直到图中不再存在W为止,总共进行DFS的次数就是答案.8个方向对应8个状态转移,每个格子作为DFS的参数最多调用一次,因此时间复杂度为O(8nm)=O(nm). AC 代码: #inc…

Lake Counting Time Limit: 1000MS Memory Limit: 65536K Total Submissions: 48370 Accepted: 23775 Description Due to recent rains, water has pooled in various places in Farmer John's field, which is represented by a rectangle of N x M (1 <= N <= 100; 1…

好吧前几天一直没更新博客,主要是更新博客的确是要耗费一点精力 北大教你数水坑 最近更新博客可能就是一点旧的东西和一些水题,主要是最近对汇编感兴趣了嘻嘻嘻 这一题挺简单的,没什么难度,简单深搜 #include <stdio.h> #include <stdlib.h> typedef int Postion; ][]; static int N, M; void DFS(Postion, Postion); int main(void) { ; while (~scanf(&quo…

Description Due to recent rains, water has pooled in various places in Farmer John's field, which is represented by a rectangle of N x M (1 <= N <= 100; 1 <= M <= 100) squares. Each square contains either water ('W') or dry land ('.'). Farmer…

Lake Counting Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 40370   Accepted: 20015 Description Due to recent rains, water has pooled in various places in Farmer John's field, which is represented by a rectangle of N x M (1 <= N <= 10…

Lake Counting Time Limit: 1000MS     Memory Limit: 65536K Total Submissions: 17917     Accepted: 9069 Description Due to recent rains, water has pooled in various places in Farmer John's field, which is represented by a rectangle of N x M (1 <= N <=…

Lake Counting Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 18201   Accepted: 9192 Description Due to recent rains, water has pooled in various places in Farmer John's field, which is represented by a rectangle of N x M (1 <= N <= 100…

-->Lake Counting 直接上中文了 Descriptions: 由于近日阴雨连天,约翰的农场中中积水汇聚成一个个不同的池塘,农场可以用 N x M (1 <= N <= 100; 1 <= M <= 100) 的正方形来表示.农场中的每个格子可以用'W'或者是'.'来分别代表积水或者土地,约翰想知道他的农场中有多少池塘.池塘的定义:一片相互连通的积水.任何一个正方形格子被认为和与它相邻的8个格子相连. 给你约翰农场的航拍图,确定有多少池塘 Input Line 1…

来之不易的2017第一发ac http://poj.org/problem?id=2386 Lake Counting Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 31474   Accepted: 15724 Description Due to recent rains, water has pooled in various places in Farmer John's field, which is repr…

Lake Counting Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 49414   Accepted: 24273 Description Due to recent rains, water has pooled in various places in Farmer John's field, which is represented by a rectangle of N x M (1 <= N <= 10…

Description There are n distinct points in the plane, given by their integer coordinates. Find the number of parallelograms whose vertices lie on these points. In other words, find the number of 4-element subsets of these points that can be written a…

题目: http://ac.jobdu.com/problem.php?pid=1481 http://acm.nyist.net/JudgeOnline/problem.php?pid=129 http://poj.org/problem?id=1308 http://acm.hdu.edu.cn/showproblem.php?pid=1272 题目意思就是判断一些给定的支点构成的树是不是一颗合法的树, 判断是不是一颗合法的树如下: 1.该树只有一个根节点 2.不存在环 对于上述两种情况采用…

lightoj 1148 Mad Counting 链接:http://lightoj.com/volume_showproblem.php?problem=1148 题意:民意调查,每一名公民都有盟友,问最少人数. 思路:考察的知识点有两个:第一是整数相乘取上整:第二是容器大小(ps:不能算一个知识点,只能算一个坑点). 做题思路:排序,如果被调查的人有相同盟友人数(n)的个数(cnt)大于这个数+1,即:(cnt > n+1), 容器已满,只能新开辟一个容器来装盟友. 代码: #includ…

描述 The cows have once again tried to form a startup company, failing to remember from past experience t hat cows make terrible managers!The cows, conveniently numbered 1-N1-N (1≤N≤100,000), organize t he company as a tree, with cow 1 as the president…

链接:http://poj.org/problem?id=2386 题解 #include<cstdio> #include<stack> using namespace std; ,MAX_N=; char a[MAX_N][MAX_M]; int N,M; //现在位置 (x,y) void dfs(int x,int y){ a[x][y]='.'; //将现在所在位置替换为'.',即旱地 ;dx<=;dx++){ //循环遍历连通的8个方向:上.下.左.右.左上.左下…

Description Due to recent rains, water has pooled in various places in Farmer John's field, which is represented by a rectangle of N x M (1 <= N <= 100; 1 <= M <= 100) squares. Each square contains either water ('W') or dry land ('.'). Farmer…

Time limit1000 ms Memory limit65536 kB Due to recent rains, water has pooled in various places in Farmer John's field, which is represented by a rectangle of N x M (1 <= N <= 100; 1 <= M <= 100) squares. Each square contains either water ('W')…

转载请注明出处:viewmode=contents">http://blog.csdn.net/u012860063?viewmode=contents 题目链接:http://poj.org/problem?id=1562 --------------------------------------------------------------------------------------------------------------------------------------…

Description Due to recent rains, water has pooled in various places in Farmer John's field, which is represented by a rectangle of N x M (1 <= N <= 100; 1 <= M <= 100) squares. Each square contains either water ('W') or dry land ('.'). Farmer…

很水的DFS. 为什么放上来主要是为了让自己的博客有一道DFS题解,,, #include<bits/stdc++.h> using namespace std; ][],ans,flag; char sx; void dfs(int x,int y){ ){ flag=; a[x][y]=; dfs(x-,y); dfs(x+,y); dfs(x,y-); dfs(x,y+); dfs(x-,y-); dfs(x+,y-); dfs(x-,y+); dfs(x+,y+); } } int m…

Aggregated Counting 转 : https://blog.csdn.net/cq_phqg/article/details/48417111 题解: 可以令n=1+2+2+3+3+......+ i    这个序列的长度为p 那么a[n]=1*1+2*2+3*2+...... + p*i 那么不难发现a[a[n]] = 1*1 + (2+3)*2 + (4+5)*3 + (6+7+8)*4 + ... + (pre+1 + pre+2 + ... + pre+b[p] ) * p…

DP中环形处理 对于DP中存在环的情况,大致有两种处理的方法: 对于很多的区间DP来说,很常见的方法就是把原来的环从任意两点断开(注意并不是直接删掉这条边),在复制一条一模一样的链在这条链的后方,当做线性问题来解,即可实现时间复杂度降维. 情况一:将原来的环从任意两点断开,再当做线性问题来解.情况二:添加一些特殊条件,将断开的前后强行连接起来.两种情况取其中的最优解即可.亦可以实现时间复杂度的降维. 本篇博客将对于第一种情况进行分析. 根据一道例题来探讨. POJ 1179 Polygon 题目…

  Palindrome Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 58168   Accepted: 20180 Description A palindrome is a symmetrical string, that is, a string read identically from left to right as well as from right to left. You are to write…

Language: Default Prime Path Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 11703   Accepted: 6640 Description The ministers of the cabinet were quite upset by the message from the Chief of Security stating that they would all have to c…

题目 传送门:QWQ 分析 思维要求比较高. 首先我们要把原图的逆序对q算出来. 这个树状数组或归并排序都ok(树状数组不用离散化好评) 那么翻转$[l,r]$中的数怎么做呢? 暴力过不了,我试过了. 设$ t=r-l+1 $即为区间长度 那么区间数对数量(看好是所有数对,不是逆序对)的数量就是$ k =\frac{n\times(n-1)}{2} $ 方法是我们判断一下数量k的奇偶性,如果是奇数的,那么就把$ q $的奇偶性变一变. 然后判断q的奇偶性输出就行. 为什么这样是对的呢? 首先翻转…

You are given a tree consisting of nn vertices. A number is written on each vertex; the number on vertex ii is equal to aiai. Let's denote the function g(x,y)g(x,y) as the greatest common divisor of the numbers written on the vertices belonging to th…

青蛙的约会 Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 103802   Accepted: 20198 Description 两只青蛙在网上相识了,它们聊得很开心,于是觉得很有必要见一面.它们很高兴地发现它们住在同一条纬度线上,于是它们约定各自朝西跳,直到碰面为止.可是它们出发之前忘记了一件很重要的事情,既没有问清楚对方的特征,也没有约定见面的具体位置.不过青蛙们都是很乐观的,它们觉得只要一直朝着某个方向跳下去,总…

Description Building and maintaining roads among communities in the far North is an expensive business. With this in mind, the roads are build such that there is only one route from a village to a village that does not pass through some other village…

Prime Path Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 15325   Accepted: 8634 Description The ministers of the cabinet were quite upset by the message from the Chief of Security stating that they would all have to change the four-dig…