http://poj.org/problem?id=1018 题意: 某公司要建立一套通信系统,该通信系统需要n种设备,而每种设备分别可以有m1.m2.m3.....mn个厂家提供生产,而每个厂家生产的同种设备都会存在两个方面的差别:带宽bandwidths 和 价格prices. 现在每种设备都各需要1个,考虑到性价比问题,要求所挑选出来的n件设备,要使得B/P最大. 其中B为这n件设备的带宽的最小值,P为这n件设备的总价. 思路:DP解决. d[i][j]代表选择第i个设备时最小带宽j时的价…

We have received an order from Pizoor Communications Inc. for a special communication system. The system consists of several devices. For each device, we are free to choose from several manufacturers. Same devices from two manufacturers differ in the…

Description We have received an order from Pizoor Communications Inc. for a special communication system. The system consists of several devices. For each device, we are free to choose from several manufacturers. Same devices from two manufacturers d…

Description We have received an order from Pizoor Communications Inc. for a special communication system. The system consists of several devices. For each device, we are free to choose from several manufacturers. Same devices from two manufacturers d…

[POJ 3071] Football(DP) Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 4350   Accepted: 2222 Description Consider a single-elimination football tournament involving 2n teams, denoted 1, 2, -, 2n. In each round of the tournament, all tea…

个人心得:百度推荐的简单DP题,自己做了下发现真得水,看了题解发现他们的思维真得比我好太多太多, 这是一段漫长的锻炼路呀. 关于这道题,我最开始用DP的思路,找子状态,发现自己根本就不会找DP状态数组建立,怎么找都是被后面的给打乱了, 看到了网上的DP[i][j],i表示前几个设备,宽带为j的最少花费,哇,真得厉害,突然发现动态规划并不需要做到问题很完美, 其实只要解决方案能够顺带把这个解决就好了. 他的这个转移方程就是,当i等于1时,输入的想,输入的x,y(x表示宽带长度,y表示价格)dp[i…

Description A plotter is a vector graphics printing device that connects to a computer to print graphical plots. There are two types of plotters: pen plotters and electrostatic plotters. Pen plotters print by moving a pen across the surface of a piec…

题意:有两棵树,标号为1和2,在Tmin内,每分钟都会有一个苹果从其中一棵树上落下,问最多移动M次的情况下(该人可瞬间移动),最多能吃到多少苹果.假设该人一开始在标号为1的树下. 分析: 1.dp[x][y][z]---第x分钟移动了y次的情况下,现在位于标号为z的树下最多吃到的苹果数. 2.枚举所有的时间.次数和可能位于的树下. 若第i分钟该人位于标号为k的树下,第i + 1分钟苹果从标号为a[i+1]的树上落下. (1)k==a[i], 此人站在标号为k的树下不移动,即可再吃到一个苹果:dp…

点击打开链接 Communication System Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 21007   Accepted: 7449 Description We have received an order from Pizoor Communications Inc. for a special communication system. The system consists of several d…

Communication System Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 21631   Accepted: 7689 Description We have received an order from Pizoor Communications Inc. for a special communication system. The system consists of several devices.…

Communication System Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 22380   Accepted: 7953 Description We have received an order from Pizoor Communications Inc. for a special communication system. The system consists of several devices.…

http://poj.org/problem?id=1260 Pearls Time Limit: 1000MS   Memory Limit: 10000K Total Submissions: 8474   Accepted: 4236 Description In Pearlania everybody is fond of pearls. One company, called The Royal Pearl, produces a lot of jewelry with pearls…

http://poj.org/problem?id=2192 Zipper Time Limit: 1000MS   Memory Limit: 65536K Total Submissions: 17585   Accepted: 6253 Description Given three strings, you are to determine whether the third string can be formed by combining the characters in the…

题目链接 题意 : 中文题不详述. 思路 : 黑书上116页讲的很详细.不过你需要在之前预处理一下面积,那样的话之后列式子比较方便一些. 先把均方差那个公式变形, 另X表示x的平均值,两边平方得 平均值是一定的,所以只要让每个矩形的总分的平方和尽量小即可.左上角坐标为(x1,y1)右下角坐标为(x2,y2)的棋盘,设总和为s[][][][],切割k次以后得到k+1块矩形的总分平方和是d[k][][][][],则可以沿着横线切也可以沿着竖线切,然后选一块接着切,递归下去,状态转移方程 d[k,x1…

Longest Ordered Subsequence Time Limit: 2000MS   Memory Limit: 65536K Total Submissions: 34454   Accepted: 15135 Description A numeric sequence of ai is ordered if a1 < a2 < ... < aN. Let the subsequence of the given numeric sequence (a1, a2, ...…

 Description Keeping track of all the cows can be a tricky task so Farmer John has installed a system to automate it. He has installed on each cow an electronic ID tag that the system will read as the cows pass by a scanner. Each ID tag's contents…

看题传送门:http://poj.org/problem?id=1018 题目大意: 某公司要建立一套通信系统,该通信系统需要n种设备,而每种设备分别可以有m个厂家提供生产,而每个厂家生产的同种设备都会存在两个方面的差别:带宽bandwidths 和 价格prices. 现在每种设备都各需要1个,考虑到性价比问题,要求所挑选出来的n件设备,要使得B/P最大. 其中B为这n件设备的带宽的最小值,P为这n件设备的总价. 思路: 贪心+枚举 要使得B/P最大,则B应该尽量大,而P尽量小. 可以按照价格…

题目链接 题意 : n×m的矩阵,每个格子中有两种矿石,第一种矿石的的收集站在最北,第二种矿石的收集站在最西,需要在格子上安装南向北的或东向西的传送带,但是每个格子中只能装一种传送带,求最多能采多少矿. 思路 :记忆化搜索.也可以用递推. #include <stdio.h> #include <string.h> #include <iostream> using namespace std ; ][] ,blog[][] ; ][] ; int DP(int row…

题目链接 题意 :给你一个字符串,让你删除或添加某些字母让这个字符串变成回文串,删除或添加某个字母要付出相应的代价,问你变成回文所需要的最小的代价是多少. 思路 :DP[i][j]代表的是 i 到 j 这一段位置变成回文所需的最小的代价. #include <stdio.h> #include <string.h> #include <iostream> using namespace std ; ] ; ] ; ][] ; int main() { int M,N ;…

Description Bessie ≤ N ≤ ,,) hours (conveniently labeled ..N-) so that she produces as much milk as possible. Farmer John has a list of M ( ≤ M ≤ ,) possibly overlapping intervals ≤ starting_houri ≤ N), an ending hour (starting_houri < ending_houri ≤…

本题一看似乎是递归回溯剪枝的方法.我一提交,结果超时. 然后又好像是使用DP,还可能我剪枝不够. 想了非常久,无奈忍不住偷看了下提示.发现方法真多.有贪心,DP,有高级剪枝的.还有三分法的.八仙过海各显神通啊. 坏习惯了,没思考够深入就偷看提示了. 幸好及时回头,还不须要看别人的代码了.自己做出来之后,有空看看多种解法的代码也好. 然后我想出自己的思路了,使用贪心,剪枝,DP综合优化下,呵呵.最后程序有点复杂.优化到了16ms,运气好点,或者vector换成原始数组的话,应该能够0MS了. 整体…

/* 一开始想的二维的 只维护第几只牛还有圈数 后来发现每只牛的能量是跟随每个状态的 所以再加一维 f[i][j][k]表示第i只牛 领跑的j全 已经消耗了k体力 转移的话分两类 1.换一只牛领跑 那么就从f[i][j][k]转移到f[i+1][j][j] 2.不换 那就枚举i领跑几圈l f[i][j-l][k-l*l]转移到f[i][j][k] 时间++ */ #include<iostream> #include<cstdio> #include<cstring>…

问题 L: Common Subsequence 时间限制: 1 Sec  内存限制: 32 MB 提交: 70  解决: 40 [提交][状态][讨论版] 题目描述 A subsequence of a given sequence is the given sequence with some elements (possible none) left out. Given a sequence X = <x1, x2, ..., xm> another sequence Z = <…

题意:问长度为L的所有01串中,有多少个不包含"101"和"111"的串. 解法:f[i][j]表示长度为i的01串中,结尾2位的十进制数是j的合法串的个数.那么,便由f[i-1][ ]逐个推出. 1 #include<cstdio> 2 #include<cstdlib> 3 #include<cstring> 4 #include<iostream> 5 using namespace std; 6 #define…

POJ 3669 Meteor Shower(流星雨) Time Limit: 1000MS    Memory Limit: 65536K Description 题目描述 Bessie hears that an extraordinary meteor shower is coming; reports say that these meteors will crash into earth and destroy anything they hit. Anxious for her sa…

注意:不要再return 的语句之后加,那样就执行不到了. system() 是调用系统命令:pause 暂停命令: 如果加有  system(”pause“): 这样在运行到此处时,会显示“Press any key to continue . . .” 也就是 “按任意键继续...”: 在VC 6.0下,要添加如下的头文件! #include <stdlib.h>   在c++  程序中用#include<iostream>也可以…

LightOJ 1033  Generating Palindromes(dp) 题目链接:http://acm.hust.edu.cn/vjudge/contest/view.action?cid=87730#problem/A 题目: Description By definition palindrome is a string which is not changed when reversed. "MADAM" is a nice example of palindrome.…

lightOJ 1047   Neighbor House (DP) 题目链接:http://acm.hust.edu.cn/vjudge/contest/view.action?cid=87730#problem/C 题目: Description The people of Mohammadpur have decided to paint each of their houses red, green, or blue. They've also decided that no two n…

UVA11125 - Arrange Some Marbles(dp) option=com_onlinejudge&Itemid=8&category=24&page=show_problem&problem=2066" target="_blank" style="">题目链接 题目大意:给你n种不同颜色的弹珠.然后给出每种颜色的弹珠的个数,如今要求你将这些弹珠排序,要求同样颜色的部分最多3个.然后同样颜色的弹珠称…

POJ 3253 Fence Repair (优先队列) Farmer John wants to repair a small length of the fence around the pasture. He measures the fence and finds that he needsN (1 ≤ N ≤ 20,000) planks of wood, each having some integer lengthLi (1 ≤ Li ≤ 50,000) units. He the…