Alex

Problem DescriptionCC always becomes very depressed at the end of this month, he has checked his credit card yesterday, without any surprise, there are only 99.9 yuan left. he is too distressed and

Problem DescriptionGiven two sequences of numbers : a[1], a[2], ...... , a[N], and b[1], b[2], ...... , b[M] (1 <= M <= 10000, 1 <= N <= 1000000). Your task is to find a number K which make a[K] =

Problem DescriptionThere is going to be a party to celebrate the 80-th Anniversary of the Ural State University. The University has a hierarchical structure of employees. It means that the supervis

Problem DescriptionGiven a two-dimensional array of positive and negative integers, a sub-rectangle is any contiguous sub-array of size 1 x 1 or greater located within the whole array. The sum of a

感觉很久没看母函数了，今天复习了下。（1+X+X^2+X^3+.....）*（）*（）*（）*（），一个括号代表一个多项式，一般可以用母函数解决一类方案数的问题，用指数代表方案的状态，系数为方案的个数。详见HDU1028代码。#include#define maxn 123 int c1[maxn], c2[maxn];int main(){ int n; while(~scanf("

Problem Description In China, foreign brand commodities are often much more expensive than abroad. The main reason is that we Chinese people tend to think foreign things are better and we are willi

Problem Description　　威威猫最近不务正业，每天沉迷于游戏“打地鼠”。　　每当朋友们劝他别太着迷游戏，应该好好工作的时候，他总是说，我是威威猫，猫打老鼠就是我的工作！　　无话可说...　　　　我们知道，打地鼠是一款经典小游戏，规则很简单：每隔一个时间段就会从地下冒出一只或多只地鼠，玩游戏的人要做的就是打地鼠。　　假设：　　1、每一个时刻我们只能打一只地鼠，并且打完以后该时刻出现

Problem DescriptionThere are a lot of trees in HDU. Kiki want to surround all the trees with the minimal required length of the rope . As follow, To make this problem more simple, consider all the

Problem Description杭州人称那些傻乎乎粘嗒嗒的人为62（音：laoer）。杭州交通管理局经常会扩充一些的士车牌照，新近出来一个好消息，以后上牌照，不再含有不吉利的数字了，这样一来，就可以消除个别的士司机和乘客的心理障碍，更安全地服务大众。不吉利的数字为所有含有4或62的号码。例如：62315 73418 88914都属于不吉利号码。但是，61152虽然含有6和2，但不是62

Problem Description Nowadays, we all know that Computer College is the biggest department in HDU. But, maybe you don't know that Computer College had ever been split into Computer College and Softw

Problem DescriptionHomer: Marge, I just figured out a way to discover some of the talents we weren’t aware we had.Marge: Yeah, what is it?Homer: Take me for example. I want to find out if I have a

Problem DescriptionDo you have spent some time to think and try to solve those unsolved problem after one ACM contest?No? Oh, you must do this when you want to become a "Big Cattle".Now you will fi

Problem Description　　小明和他的好朋友小西在玩一个新的游戏，由小西给出一个由小写字母构成的字符串，小明给出另一个比小西更长的字符串，也由小写字母组成，如果能通过魔法转换使小明的串和小西的变成同一个，那么他们两个人都会很开心。这里魔法指的是小明的串可以任意删掉某个字符，或者把某些字符对照字符变化表变化。如：　　　　小西的串是 abba;　　　　小明的串是 addba; 　　　

Problem DescriptionMario is world-famous plumber. His “burly” figure and amazing jumping ability reminded in our memory. Now the poor princess is in trouble again and Mario needs to save his lover.

Problem Description　　在Windows下我们可以通过cmd运行DOS的部分功能，其中CD是一条很有意思的命令，通过CD操作，我们可以改变当前目录。　　这里我们简化一下问题，假设只有一个根目录，CD操作也只有两种方式：　　　　1. CD 当前目录名\...\目标目录名 (中间可以包含若干目录，保证目标目录通过绝对路径可达)　　2. CD .. (返回当前目录的

Caocao's BridgesTime Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 1417    Accepted Submission(s): 541Problem DescriptionCaocao was def

Problem DescriptionRecently, scientists find that there is love between any of two people. For example, between A and B, if A don’t love B, then B must love A, vice versa. And there is no possibilit

Problem DescriptionACM-DIY is a large QQ group where many excellent acmers get together. It is so harmonious that just like a big family. Every day,many "holy cows" like HH, hh, AC, ZT, lcc, BF, Qin

Problem DescriptionConsider a group of N students and P courses. Each student visits zero, one or more than one courses. Your task is to determine whether it is possible to form a committee of exact

Problem DescriptionThere are a group of students. Some of them may know each other, while others don't. For example, A and B know each other, B and C know each other. But this may not imply that A a

Here We Go(relians) AgainTime Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 711    Accepted Submission(s): 347Problem DescriptionThe Go

Problem DescriptionJimmy is studying Advanced Graph Algorithms at his university. His most recent assignment is to find a maximum matching in a special kind of graph. This graph is undirected, has N

Problem Description　　Some 1×2 dominoes are placed on a plane. Each dominoe is placed either horizontally or vertically. It's guaranteed the dominoes in the same direction are not overlapped, but hor

Problem DescriptionA segment and all segments which are connected with it compose a segment set. The size of a segment set is the number of segments in it. The problem is to find the size of some se

Problem DescriptionSome of the secret doors contain a very interesting word puzzle. The team of archaeologists has to solve it to open that doors. Because there is no other way to open the doors, th

Problem DescriptionMr Wang wants some boys to help him with a project. Because the project is rather complex,the more boys come, the better it will be. Of course there are certain requirements.

Problem Description  This year is the 60th anniversary of NJUST, and to make the celebration more colorful, Tom200 is going to invite distinguished alumnus back to visit and take photos.  Af

Problem Description传说在遥远的地方有一个非常富裕的村落,有一天,村长决定进行制度改革：重新分配房子。这可是一件大事,关系到人民的住房问题啊。村里共有n间房间,刚好有n家老百姓,考虑到每家都要有房住（如果有老百姓没房子住的话，容易引起不安定因素），每家必须分配到一间房子且只能得到一间房子。另一方面,村长和另外的村领导希望得到最大的效益,这样村里的机构才会有钱.由于老百

Problem DescriptionRobbie is playing an interesting computer game. The game field is an unbounded 2-dimensional region. There are N rounds in the game. At each round, the computer will give Robbie t

Problem DescriptionOne day, Lin Ji wake up in the morning and found that his pethamster escaped. He searched in the room but didn’t find the hamster. He tried to use some cheese to trap the hamster.

Max SumTime Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 147262    Accepted Submission(s): 34418Problem DescriptionGiven a sequence a[

Revenge of GCDTime Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)Total Submission(s): 226    Accepted Submission(s): 66Problem DescriptionIn mathematics, th

Problem DescriptionCaptain Clearbeard decided to go to the harbour for a few days so his crew could inspect and repair the ship. Now, a few days later, the pirates are getting landsick(Pirates get l

Problem DescriptionYesterday, my teacher taught me about bit operators: and (&), or (|), xor (^). I generated a number table a[N], and wrote a program to calculate the matrix table b[N][N] using thr

Problem DescriptionThe inversion number of a given number sequence a1, a2, ..., an is the number of pairs (ai, aj) that satisfy i aj.For a given sequence of numbers a1, a2, ..., an, if we move

Problem DescriptionThe Princess has been abducted by the BEelzebub feng5166, our hero Ignatius has to rescue our pretty Princess. Now he gets into feng5166's castle. The castle is a large labyrinth.

Problem DescriptionPass a year learning in Hangzhou, yifenfei arrival hometown Ningbo at finally. Leave Ningbo one year, yifenfei have many people to meet. Especially a good friend Merceki.Yifenfe

Problem DescriptionSherlock's N (1 ≤ N ≤ 100,000) cows are lined up to be milked in the evening. Each cow has a unique "grumpiness" level in the range 1...100,000. Since grumpy cows are more likely

Problem DescriptionFor the k-th number, we all should be very familiar with it. Of course,to kiki it is also simple. Now Kiki meets a very similar problem, kiki wants to design a container, the cont

Asteroids!Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 3497    Accepted Submission(s): 2312Problem DescriptionYou're in space.Y