WOLF的博客

DescriptionImagine you are attending your math lesson at school. Once again, you are bored because your teacher tells things that you already mastered years ago (this time he's explaining that (a+

Problem DescriptionThere are many lamps in a line. All of them are off at first. A series of operations are carried out on these lamps. On the i-th operation, the lamps whose numbers are the multipl

Problem Description你活的不容易，我活的不容易，他活的也不容易。不过，如果你看了下面的故事，就会知道，有位老汉比你还不容易。重庆市郊黄泥板村的徐老汉（大号徐东海，简称XDH）这两年辛辛苦苦养了不少羊，到了今年夏天，由于众所周知的高温干旱，实在没办法解决牲畜的饮水问题，就决定把这些羊都赶到集市去卖。从黄泥板村到交易地点要经过N个收费站，按说这收费站和徐老汉没什么关系，但

Problem Description古希腊数学家毕达哥拉斯在自然数研究中发现，220的所有真约数(即不是自身的约数)之和为： 1+2+4+5+10+11+20+22+44+55+110＝284。 而284的所有真约数为1、2、4、71、 142，加起来恰好为220。人们对这样的数感到很惊奇，并称之为亲和数。一般地讲，如果两个数中任何一个数都是另一个数的真约数之和，则这两个

Problem DescriptionGive you the width and height of the rectangle,darw it. InputInput contains a number of test cases.For each case ,there are two numbers n and m (0  OutputFor each

Palindromes _easy versionTime Limit: 2000/1000 MS (Java/Others)    Memory Limit: 65536/32768 K (Java/Others)Total Submission(s): 34342    Accepted Submission(s): 20863Problem Description“回

Problem Description“ 改革春风吹满地,不会AC没关系;实在不行回老家，还有一亩三分地。谢谢!（乐队奏乐）”话说部分学生心态极好，每天就知道游戏，这次考试如此简单的题目，也是云里雾里，而且，还竟然来这么几句打油诗。好呀，老师的责任就是帮你解决问题，既然想种田，那就分你一块。这块田位于浙江省温州市苍南县灵溪镇林家铺子村，多边形形状的一块地，原本是

Problem Description网上流传一句话:"常在网上飘啊，哪能不挨刀啊～"。其实要想能安安心心地上网其实也不难，学点安全知识就可以。首先，我们就要设置一个安全的密码。那什么样的密码才叫安全的呢？一般来说一个比较安全的密码至少应该满足下面两个条件：(1).密码长度大于等于8，且不要超过16。(2).密码中的字符应该来自下面“字符类别”中四组中的至少三组。

DescriptionGiven two integers: n and m and n is divisible by 2m, you have to write down the first n natural numbers in the following form. At first take first mintegers and make their sign negat

DescriptionFibsieve had a fantabulous (yes, it's an actual word) birthday party this year. He had so many gifts that he was actually thinking of not having a party next year.Among these gifts th

Problem DescriptionAs we know, Big Number is always troublesome. But it's really important in our ACM. And today, your task is to write a program to calculate A mod B.To make the problem easier,

Problem DescriptionA range is given, the begin and the end are both integers. You should sum the cube of all the integers in the range. InputThe first line of the input is T(1 Each case of

Euler is a well-known matematician, and, among many other things, he discovered that the formulan2 + n + 41 produces a prime for 0 ≤ n < 40. For n = 40, the formula produces 1681, which is 41 ∗ 41.Eve

Problem DescriptionWhen Teddy was a child , he was always thinking about some simple math problems ,such as “What it’s 1 cup of water plus 1 pile of dough ..” , “100 yuan buy 100 pig” .etc..On

Vasiliy lives at point (a, b) of the coordinate plane. He is hurrying up to work so he wants to get out of his house as soon as possible. New app suggested n available Beru-taxi nearby. The i-th t

DescriptionYou are given an array of n elements, you must make it a co-prime array in as few moves as possible.In each move you can insert any positive integral number you want not greater than 

DescriptionKefa wants to celebrate his first big salary by going to restaurant. However, he needs company.Kefa has n friends, each friend will agree to go to the restaurant if Kefa asks. Each fr

DescriptionHDD hard drives group data by sectors. All files are split to fragments and each of them are written in some sector of hard drive. Note the fragments can be written in sectors in arbitr

DescriptionVasya wants to turn on Christmas lights consisting of m bulbs. Initially, all bulbs are turned off. There are n buttons, each of them is connected to some set of bulbs. Vasya can pres

DescriptionPasha has a wooden stick of some positive integer length n. He wants to perform exactly three cuts to get four parts of the stick. Each part must have some positive integer length and t

DescriptionKevin Sun has just finished competing in Codeforces Round #334! The round was 120 minutes long and featured five problems with maximum point values of 500, 1000, 1500, 2000, and 2500, r

DescriptionFind the number of k-divisible numbers on the segment [a, b]. In other words you need to find the number of such integer values xthat a ≤ x ≤ b and x is divisible by k.Input

Problem Description参加过上个月月赛的同学一定还记得其中的一个最简单的题目，就是{A}+{B}，那个题目求的是两个集合的并集，今天我们这个A-B求的是两个集合的差，就是做集合的减法运算。（当然，大家都知道集合的定义，就是同一个集合中不会有两个相同的元素，这里还是提醒大家一下）呵呵，很简单吧？ Input每组输入数据占1行,每行数据的开始是2个整数n(0

DescriptionIn this problem you are to calculate the sum of all integers from 1 to n, but you should take all powers of two with minus in the sum.For example, for n = 4 the sum is equal to  - 1 -

DescriptionFriends are going to play console. They have two joysticks and only one charger for them. Initially first joystick is charged at a1percent and second one is charged at a2 percent. You

DescriptionThere are n pictures delivered for the new exhibition. The i-th painting has beauty ai. We know that a visitor becomes happy every time he passes from a painting to a more beautiful o

DescriptionVasya likes everything infinite. Now he is studying the properties of a sequence s, such that its first element is equal to a (s1 = a), and the difference between any two neighbouring

DescriptionVasya works as a watchman in the gallery. Unfortunately, one of the most expensive paintings was stolen while he was on duty. He doesn't want to be fired, so he has to quickly restore t

DescriptionBear Limak likes watching sports on TV. He is going to watch a game today. The game lasts 90 minutes and there are no breaks.Each minute can be either interesting or boring. If 15 con

DescriptionThere are n problems prepared for the next Codeforces round. They are arranged in ascending order by their difficulty, and no two problems have the same difficulty. Moreover, there are 

DescriptionLittle Artem got n stones on his birthday and now wants to give some of them to Masha. He knows that Masha cares more about the fact of receiving the present, rather than the value of t

DescriptionOn the planet Mars a year lasts exactly n days (there are no leap years on Mars). But Martians have the same weeks as earthlings — 5 work days and then 2 days off. Your task is to deter

DescriptionA lot of people in Berland hates rain, but you do not. Rain pacifies, puts your thoughts in order. By these years you have developed a good tradition — when it rains, you go on the stre

DescriptionToday, Wet Shark is given n bishops on a 1000 by 1000 grid. Both rows and columns of the grid are numbered from 1 to 1000. Rows are numbered from top to bottom, while columns are numb

DescriptionWatchmen are in a danger and Doctor Manhattan together with his friend Daniel Dreiberg should warn them as soon as possible. There are n watchmen on a plane, the i-th watchman is loca

J - FootballTime Limit:2000MS     Memory Limit:262144KB     64bit IO Format:%I64d & %I64uSubmit StatusDescriptionPetya loves football very much. One day, as he was watching a footb

DescriptionNothing has changed since the last round. Dima and Inna still love each other and want to be together. They've made a deal with Seryozha and now they need to make a deal with the dorm g

DescriptionVasya lives in a round building, whose entrances are numbered sequentially by integers from 1 to n. Entrance n and entrance 1 are adjacent.Today Vasya got bored and decided to take

DescriptionThe main street of Berland is a straight line with n houses built along it (n is an even number). The houses are located at both sides of the street. The houses with odd numbers are a

DescriptionLimak is a little polar bear. He has n balls, the i-th ball has size ti.Limak wants to give one ball to each of his three friends. Giving gifts isn't easy — there are two rules Limak