codeforces 424D Biathlon Track 题意 题解 代码 #include<bits/stdc++.h> using namespace std; #define fi first #define se second #define mp make_pair #define pb push_back #define rep(i, a, b) for(int i=(a); i<(b); i++) #define sz(a) (int)a.size() #define…

Codeforces Round #242 (Div. 2) D:http://codeforces.com/contest/424/problem/D 题意:给你一个n*m的矩阵,每个格子上面有个数字,在相邻格子之间会有一定的费用,费用根据相邻格子的大小关系确定.让你费用最接近一个数的矩阵. 题解:一看题目,想了一下,预处理,然后猜到要用二分.但是二维的怎么二分,一直没有想到什么办法,一直想的是(n*mlog(n*m))的算法,所以不对了.其实应该固定一个起点,作为矩阵的左上角的点,然后枚举右…

题目大概说给两个串,问最少要用多少个第一个串的子串(可以翻转)拼成第二个串. UVa1401,一个道理..dp[i]表示前缀i拼接成功所需最少的子串,利用第一个串所有子串建立的Trie树往前枚举转移. #include<cstdio> #include<cstdlib> using namespace std; #define MAXN 2222*2000 ],from[MAXN],to[MAXN]; ],S[]; ],rec[]; void pnt(int x){ ) retur…

题意:给定n,m<=300的矩阵,然后求一个长宽大于2的矩形,使得是从左上角位置开始逆时针绕边框一圈的时间最少.时间的计算是:给定3个数tu,tp, td,路径上数字增加为tu,相等为tp否则为td. 思路:直接预处理出4个数组,然后直接暴力.n4的方法.但是常数小可以4000+ms过. 还有一种n3logn的方法.. 具体是固定右下角,然后枚举右上角,然后通过一个通过地推维护一个前缀,二分查找.. 不过常数肯定比暴力大估计快不了多少.. code: #include <bits/stdc++…

题意:给出一个n*m的矩阵,内有一些数字.当你从一个方格走到另一个方格时,按这两个方格数字的大小,有(升,平,降)三种费用.你需要在矩阵中找到边长大于2的一个矩形,使得按这个矩形顺时针行走一圈的费用,与给定费用最接近.3<=n,m<=300. 思路:O(1)计算一个矩形的费用不是什么难事,因为考虑到有前缀性质(前缀性质:[l,r] = [0,r] - [0,l-1]),只要预处理好各行各个方向行走的费用,就容易计算. 直接枚举容易得到O(n^4)的算法.难以过.这时就应当想到优化.实际上,经过…

CF424 A. Squats 题目意思: 有n(n为偶数)个x和X,求最少的变换次数,使得X的个数为n/2,输出变换后的序列. 解题思路: 统计X的个数ans,和n/2比較,少了的话,须要把n/2-ans个x变成X,多了的话须要把ans-n/2个X变成x.(从前往后扫一遍即可了). 代码: //#include<CSpreadSheet.h> #include<iostream> #include<cmath> #include<cstdio> #incl…

C. Running Track 题目连接: http://www.codeforces.com/contest/615/problem/C Description A boy named Ayrat lives on planet AMI-1511. Each inhabitant of this planet has a talent. Specifically, Ayrat loves running, moreover, just running is not enough for hi…

time limit per test1 second memory limit per test512 megabytes inputstandard input outputstandard output A boy named Ayrat lives on planet AMI-1511. Each inhabitant of this planet has a talent. Specifically, Ayrat loves running, moreover, just runnin…

C. Gerald's Hexagon Time Limit: 2 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/559/problem/A Description Gerald got a very curious hexagon for his birthday. The boy found out that all the angles of the hexagon are equal to . Then he me…

Problem I. Instruction 题目连接: http://codeforces.com/gym/100531/attachments Description Ingrid is a head of a big railway station and, among other duties, is responsible for routing trains to the right platforms. The station has one entrance, and there…

A. Gerald's Hexagon Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/559/problem/A Description Gerald got a very curious hexagon for his birthday. The boy found out that all the angles of the hexagon are equal to . Then he m…

Music Mess Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100463/attachments Description Francis really likes his music. He especially likes that song ’Zombie Nation’. Or was that the album? Or maybe the album was ’Kernkraft 4…

Spies Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100463/attachments Description In the aftermath of Canada’s annexation of Pittsburgh tensions have been pretty high between Canada and the US. You have personally been hired…

题目链接: http://codeforces.com/problemset/problem/208/A A. Dubstep time limit per test:2 secondsmemory limit per test:256 megabytes 问题描述 Vasya works as a DJ in the best Berland nightclub, and he often uses dubstep music in his performance. Recently, he…

H. Bots Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/575/problem/H Description Sasha and Ira are two best friends. But they aren’t just friends, they are software engineers and experts in artificial intelligence. They are…

C. Read Time Time Limit: 1 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/343/problem/C Description Mad scientist Mike does not use slow hard disks. His modification of a hard drive has not one, but n different heads that can read data i…

C - C Time Limit:2000MS     Memory Limit:262144KB     64bit IO Format:%I64d & %I64u Submit Status Practice CodeForces 569A Description Little Lesha loves listening to music via his smartphone. But the smartphone doesn't have much memory, so Lesha lis…

codeforces  569A   Music   解题报告 题目链接:http://acm.hust.edu.cn/vjudge/contest/view.action?cid=88890#problem/C 题目: Description Little Lesha loves listening to music via his smartphone. But the smartphone doesn't have much memory, so Lesha listens to his…

D. Bicycle Race 题目链接http://codeforces.com/contest/659/problem/D Description Maria participates in a bicycle race. The speedway takes place on the shores of Lake Lucerne, just repeating its contour. As you know, the lake shore consists only of straigh…

Resort Time Limit:2000MS     Memory Limit:262144KB     64bit IO Format:%I64d & %I64u Submit Status Practice CodeForces 350B Description Valera's finally decided to go on holiday! He packed up and headed for a ski resort. Valera's fancied a ski trip b…

[CF简单介绍] 提交链接:http://codeforces.com/contest/560/problem/C 题面: C. Gerald's Hexagon time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Gerald got a very curious hexagon for his birthday. The bo…

E. DNA Evolution 题目连接: http://codeforces.com/contest/828/problem/E Description Everyone knows that DNA strands consist of nucleotides. There are four types of nucleotides: "A", "T", "G", "C". A DNA strand is a seque…

C. Gerald's Hexagon time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Gerald got a very curious hexagon for his birthday. The boy found out that all the angles of the hexagon are equal to .…

Everyone knows that DNA strands consist of nucleotides. There are four types of nucleotides: "A", "T", "G", "C". A DNA strand is a sequence of nucleotides. Scientists decided to track evolution of a rare species, wh…

B. Dasha and friends 题目连接: http://codeforces.com/contest/761/problem/B Description Running with barriers on the circle track is very popular in the country where Dasha lives, so no wonder that on her way to classes she saw the following situation: Th…

原题: http://codeforces.com/contest/569/problem/B 题目: Inventory time limit per test1 second memory limit per test256 megabytes inputstandard input outputstandard output Companies always have a lot of equipment, furniture and other things. All of them s…

C. Mike and Chocolate Thieves time limit per test:2 seconds memory limit per test:256 megabytes input:standard input output:standard output Bad news came to Mike's village, some thieves stole a bunch of chocolates from the local factory! Horrible! As…

C. Mike and Chocolate Thieves 题目连接: http://www.codeforces.com/contest/689/problem/C Description Bad news came to Mike's village, some thieves stole a bunch of chocolates from the local factory! Horrible! Aside from loving sweet things, thieves from t…

C. Gerald and Giant Chess Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/559/problem/C Description Gerald got a very curious hexagon for his birthday. The boy found out that all the angles of the hexagon are equal to . The…

D. Bicycle Race 题目连接: http://www.codeforces.com/contest/659/problem/D Description Maria participates in a bicycle race. The speedway takes place on the shores of Lake Lucerne, just repeating its contour. As you know, the lake shore consists only of s…