C. Memory and De-Evolution 题目连接: http://codeforces.com/contest/712/problem/C Description Memory is now interested in the de-evolution of objects, specifically triangles. He starts with an equilateral triangle of side length x, and he wishes to perfor…

B. Memory and Trident 题目连接: http://codeforces.com/contest/712/problem/B Description Memory is performing a walk on the two-dimensional plane, starting at the origin. He is given a string s with his directions for motion: An 'L' indicates he should mo…

A. Memory and Crow 题目连接: http://codeforces.com/contest/712/problem/A Description There are n integers b1, b2, ..., bn written in a row. For all i from 1 to n, values ai are defined by the crows performing the following procedure: The crow sets ai ini…

Codeforces Round #297 (Div. 2)A. Vitaliy and Pie Time Limit: 2 Sec  Memory Limit: 256 MBSubmit: xxx  Solved: 2xx 题目连接 http://codeforces.com/contest/525/problem/A Description After a hard day Vitaly got very hungry and he wants to eat his favorite pot…

A. Mahmoud and Longest Uncommon Subsequence time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output While Mahmoud and Ehab were practicing for IOI, they found a problem which name was Longest comm…

题目链接: http://codeforces.com/contest/712/problem/E 题目大意: 一条直线上有n格,在第i格有pi的可能性向右走一格,1-pi的可能性向左走一格,有2中操作:单点修改pi以及询问从L格出发最终从R格离开区间[L,R]的概率. 这题在cf上A的人比较少,本来不打算去做的,然后看了下是概率的题目,比较感兴趣,就去做了下,然后发现并不会做,就搜了题解. 题解: 参考http://www.cnblogs.com/qscqesze/p/5868047.html…

E. Memory and Casinos 题目连接: http://codeforces.com/contest/712/problem/E Description There are n casinos lined in a row. If Memory plays at casino i, he has probability pi to win and move to the casino on the right (i + 1) or exit the row (if i = n),…

地址:http://codeforces.com/problemset/problem/712/C 题目: C. Memory and De-Evolution time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Memory is now interested in the de-evolution of objects, sp…

地址:http://codeforces.com/problemset/problem/712/B 题目: B. Memory and Trident time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Memory is performing a walk on the two-dimensional plane, starti…

D. Memory and Scores 题目连接: http://codeforces.com/contest/712/problem/D Description Memory and his friend Lexa are competing to get higher score in one popular computer game. Memory starts with score a and Lexa starts with score b. In a single turn, b…

A B C :=w= D:两个人得分互不影响很关键 一种是f[i][j]表示前i轮,分差为j的方案数 明显有f[i][j]=f[i-1][j-2k]+2*f[i-1][j-2k+1]+...+(2k+1)f[i-1][j]+... 枚举是K*T*T,转移是K 超时 不过发现转移的时候可以理解为j是j-1的算式的整个区间移动,于是可以维护f[i-1]的前缀和来达到O(1)的转移 另一种f[i][j]表示前i轮,某个人分数为j的方案数(两人互不影响,无先后手之分,所以两人等价) 式子写出来就少了第一…

C. Memory and De-Evolution time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Memory is now interested in the de-evolution of objects, specifically triangles. He starts with an equilateral tr…

D. Memory and Scores   Memory and his friend Lexa are competing to get higher score in one popular computer game. Memory starts with score a and Lexa starts with score b. In a single turn, both Memory and Lexa get some integer in the range [ - k;k] (…

Description Memory is now interested in the de-evolution of objects, specifically triangles. He starts with an equilateral triangle of side length x, and he wishes to perform operations to obtain an equilateral triangle of side length y. In a single…

Description Memory is performing a walk on the two-dimensional plane, starting at the origin. He is given a string s with his directions for motion: An 'L' indicates he should move one unit left. An 'R' indicates he should move one unit right. A 'U'…

Description There are n integers b1, b2, ..., bn written in a row. For all i from 1 to n, values ai are defined by the crows performing the following procedure: The crow sets ai initially 0. The crow then adds bi to ai, subtracts bi + 1, adds the bi …

A. Memory and Crow time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output There are n integers b1, b2, ..., bn written in a row. For all i from 1 to n, values ai are defined by the crows performi…

A. Memory and Crow time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output There are n integers b1, b2, ..., bn written in a row. For all i from 1 to n, values ai are defined by the crows performi…

题目链接:http://codeforces.com/problemset/problem/719/C C. Efim and Strange Grade time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Efim just received his grade for the last test. He studies in a…

A. Vladik and flights 题目链接 http://codeforces.com/contest/743/problem/A 题面 Vladik is a competitive programmer. This year he is going to win the International Olympiad in Informatics. But it is not as easy as it sounds: the question Vladik face now is…

D. Anton and Chess 题目连接: http://codeforces.com/contest/734/problem/D Description Anton likes to play chess. Also, he likes to do programming. That is why he decided to write the program that plays chess. However, he finds the game on 8 to 8 board to…

B. Anton and Digits 题目连接: http://codeforces.com/contest/734/problem/B Description Recently Anton found a box with digits in his room. There are k2 digits 2, k3 digits 3, k5 digits 5 and k6 digits 6. Anton's favorite integers are 32 and 256. He decide…

A. Anton and Danik 题目连接: http://codeforces.com/contest/734/problem/A Description Anton likes to play chess, and so does his friend Danik. Once they have played n games in a row. For each game it's known who was the winner - Anton or Danik. None of th…

B. War of the Corporations 题目连接: http://www.codeforces.com/contest/625/problem/B Description A long time ago, in a galaxy far far away two giant IT-corporations Pineapple and Gogol continue their fierce competition. Crucial moment is just around the…

B. Gena's Code 题目连接: http://www.codeforces.com/contest/614/problem/B Description It's the year 4527 and the tanks game that we all know and love still exists. There also exists Great Gena's code, written in 2016. The problem this code solves is: give…

A. Link/Cut Tree 题目连接: http://www.codeforces.com/contest/614/problem/A Description Programmer Rostislav got seriously interested in the Link/Cut Tree data structure, which is based on Splay trees. Specifically, he is now studying the expose procedure…

A. Fox And Snake 题目连接: http://codeforces.com/contest/510/problem/A Description Fox Ciel starts to learn programming. The first task is drawing a fox! However, that turns out to be too hard for a beginner, so she decides to draw a snake instead. A sna…

A. Saitama Destroys Hotel 题目连接: http://www.codeforces.com/contest/608/problem/A Description Saitama accidentally destroyed a hotel again. To repay the hotel company, Genos has volunteered to operate an elevator in one of its other hotels. The elevato…

B. Pasha and Tea Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/557/problem/B Description Pasha decided to invite his friends to a tea party. For that occasion, he has a large teapot with the capacity of w milliliters and…

A. Ilya and Diplomas Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/557/problem/A Description Soon a school Olympiad in Informatics will be held in Berland, n schoolchildren will participate there. At a meeting of the jury…