题目链接: http://codeforces.com/problemset/problem/337/D D. Book of Evil time limit per test2 secondsmemory limit per test256 megabytes 问题描述 Paladin Manao caught the trail of the ancient Book of Evil in a swampy area. This area contains n settlements num…

A - Ostap and Grasshopper zz题能不能跳到  每次只能跳K步 不能跳到# 问能不能T-G  随便跳跳就可以了  第一次居然跳越界0.0  傻子哦  WA1 n,k = map(int,input().split()) s = input() i = 0 st = -1 def jump(st): while(st<n): st+=k if(st>=n or s[st]=='#'): return "NO" if(s[st]=='T' or s[st…

题意:给了一棵树以及每个节点的颜色,1代表黑,0代表白,求将这棵树拆成k棵树,使得每棵树恰好有一个黑色节点的方法数 解法:树形DP问题.定义: dp[u][0]表示以u为根的子树对父亲的贡献为0 dp[u][1]表示以u为根的子树对父亲的贡献为1 现在假设u为白色,它的子树有x,y,z,那么有 dp[u][1]+=dp[x][1]*dp[y][0]*dp[z][0]+dp[x][0]*dp[y][1]*dp[z][0]+dp[x][0]*dp[y][0]*dp[z][1] dp[u][0]+=d…

C. Karen and Supermarket     On the way home, Karen decided to stop by the supermarket to buy some groceries. She needs to buy a lot of goods, but since she is a student her budget is still quite limited. In fact, she can only spend up to b dollars.…

Codeforces Round #267 (Div. 2) C. George and Job题目链接请点击~ The new ITone 6 has been released recently and George got really keen to buy it. Unfortunately, he didn't have enough money, so George was going to work as a programmer. Now he faced the follow…

(CF唯一不好的地方就是时差……不过还好没去考,考的话就等着滚回Div. 2了……) A - Quiz 裸的贪心,不过要用矩阵乘法优化或者直接推通式然后快速幂.不过本傻叉做的时候脑子一片混乱,导致WA+TLE若干次,而且还做了很久(半小时)…… #include <cstdio> const int MOD = 1000000000+9; int ans,n,m,k; int power(long long x,int k) { int res = 1; for (;k;k >>=…

screen 尺寸为a:b video 尺寸为 c:d 如果a == c 则 面积比为 cd/ab=ad/cb (ad < cb) 如果b == d 则 面积比为 cd/ab=cb/ad  (cb < ad) 如果不相等时 如果a/b > c/d,则ad/bd > cb/db 则(ad > cb) screen尺寸可为 ad:bd, video的尺寸可为 cb:db 面积比为:cb*db/ad*bd = cb/ad (ad > cb) 如果a/b < c/d,则a…

A 题意:O(-1) 思路:排个序搞定. B 题意:O(-1) 思路:坑了我好久,这个框框水平垂直比例固定,分两种情况即可,不能旋转,我想多了,分了四种情况. C 题意:一列n个位置,让你填m个数,当连续数达到k时,分数乘以2,计数清零,当不连续时,计数也清零,没到达k之前分数+1. 思路:很显然的问题是让我们处理填m个位置,并且使连续的k个数次数最少.我们先让m个数k-1每次填,填一次空一位,直到不够填了就往前面的空位填.设连续k个次数为mm,那么就是(((2*k)+k)*2……+k)*2,等…

题目的大意是,给你 m 个数字,让你从中选 n 个,使得选出的数字的极差最小. 好吧,超级大水题.因为要极差最小,所以当然想到要排个序咯,然后去连续的 n 个数字,因为数据不大,所以排完序之后直接暴力就OK了. 附AC代码: 1: #include <stdio.h> 2: #include <math.h> 3: #include <iostream> 4: #include <cstdarg> 5: #include <algorithm>…

A. Puzzles Time Limit: 2 Sec  Memory Limit: 60 MB 题目连接 http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemId=5373 Description The end of the school year is near and Ms. Manana, the teacher, will soon have to say goodbye to a yet another class. S…

A:sort以后求差值最小 ]; int main() { int n,m; cin>>n>>m; ; i < m ; i++) cin>>a[i]; sort(a,a+m); int mm = INF; ; i+n- < m ; i++) mm = min(mm,a[i+n-]-a[i]); cout<<mm<<endl; ; } B:求屏幕黑框占屏幕的几分之几 . 求LCM后的差值 LL gcd(LL a,LL b){ retur…

A. Puzzles 对\(f[]\)排序,取连续的\(m\)个. B. Routine Problem 考虑\(\frac{a}{b}\)和\(\frac{c}{d}\)的大小关系,适配后就是分数的运算. C. Quiz 按\(k\)将\(n\)个问题分段,那么在没有分数翻倍的情况下最大题数为\[(k-1)\lfloor\frac{n}{k}\rfloor+n\%k\] 若\(m\le (k-1)\lfloor\frac{n}{k}\rfloor+n\%k\),则最大分数就为\(m\),否则翻…

C. Famil Door and Brackets 题目连接: http://www.codeforces.com/contest/629/problem/C Description As Famil Door's birthday is coming, some of his friends (like Gabi) decided to buy a present for him. His friends are going to buy a string consisted of roun…

题目链接: http://codeforces.com/problemset/problem/208/C C. Police Station time limit per test:2 secondsmemory limit per test:256 megabytes 问题描述 The Berland road network consists of n cities and of m bidirectional roads. The cities are numbered from 1 to…

B. Let's Play Osu! 题目连接: http://www.codeforces.com/contest/235/problem/B Description You're playing a game called Osu! Here's a simplified version of it. There are n clicks in a game. For each click there are two outcomes: correct or bad. Let us deno…

C. Chain Reaction 题目连接: http://www.codeforces.com/contest/608/problem/C Description There are n beacons located at distinct positions on a number line. The i-th beacon has position ai and power level bi. When the i-th beacon is activated, it destroys…

题目:https://codeforces.com/problemset/problem/977/F 题意:一个序列,求最长单调递增子序列,但是有一个要求是中间差值都是1 思路:dp,O(n)复杂度,我们想一下O(n^2)时的最长递增子序列,我们第二个循环要遍历前面所有的如果大于长度就加1,代表以这个数结尾的最长长度是多少, 因为中间差值不定,所以我们遍历整个循环,这个题设置中间差值只能是1,所以我们递推式就可以是   dp[i]=max(dp[i],dp[i-1]+1),用map来映射值即可…

C. Mahmoud and a Message 题目连接: http://codeforces.com/contest/766/problem/C Description Mahmoud wrote a message s of length n. He wants to send it as a birthday present to his friend Moaz who likes strings. He wrote it on a magical paper but he was su…

题目链接: http://codeforces.com/problemset/problem/148/D D. Bag of mice time limit per test2 secondsmemory limit per test256 megabytes 问题描述 The dragon and the princess are arguing about what to do on the New Year's Eve. The dragon suggests flying to the…

题目链接: http://codeforces.com/problemset/problem/621/E E. Wet Shark and Blocks time limit per test2 secondsmemory limit per test256 megabytes 问题描述 There are b blocks of digits. Each one consisting of the same n digits, which are given to you in the inp…

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…

http://codeforces.com/contest/754/problem/C C. Vladik and chat time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output Recently Vladik discovered a new entertainment — coding bots for social netwo…

D. Bad Luck Island Time Limit: 1 Sec  Memory Limit: 256 MB 题目连接 http://codeforces.com/contest/540/problem/D Description The Bad Luck Island is inhabited by three kinds of species: r rocks, s scissors and p papers. At some moments of time two random i…

任意门:http://codeforces.com/contest/1114/problem/D D. Flood Fill time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output You are given a line of nn colored squares in a row, numbered from 11 to nn f…

D. Brand New Problem 题目连接: http://www.codeforces.com/contest/201/problem/D Description A widely known among some people Belarusian sport programmer Lesha decided to make some money to buy a one square meter larger flat. To do this, he wants to make a…

链接: https://codeforces.com/contest/1272/problem/D 题意: You are given an array a consisting of n integers. You can remove at most one element from this array. Thus, the final length of the array is n−1 or n. Your task is to calculate the maximum possib…

链接: https://codeforces.com/contest/1215/problem/B 题意: You are given a sequence a1,a2,-,an consisting of n non-zero integers (i.e. ai≠0). You have to calculate two following values: the number of pairs of indices (l,r) (l≤r) such that al⋅al+1-ar−1⋅ar…

链接: https://codeforces.com/contest/1228/problem/E 题意: You have n×n square grid and an integer k. Put an integer in each cell while satisfying the conditions below. All numbers in the grid should be between 1 and k inclusive. Minimum number of the i-t…

题目链接:https://codeforces.com/contest/1370/problem/E 题意 给出两个长为 $n$ 的 $01$ 串 $s$ 和 $t$,每次可以选择 $s$ 的一些下标,使字符只在这些下标内循环右移一个单位,问两个字符串相等至少需要循环移动多少次. 题解 无解的情况 两个字符串中的 $01$ 个数不同. 有解的情况 将 $s$ 中同一位置与 $t$ 不同的字符拿出组成一个新字符串,每次操作一定是取这个新字符串 $01010 \dots$ 或 $10101 \dot…

题目链接:https://codeforces.com/contest/1363/problem/E 题意 有一棵 $n$ 个结点,根为结点 $1$ 的树,每个结点有一个选取代价 $a_i$,当前 $b_i$,目标数字 $c_i$ .每次可以选择以一个结点为根节点的子树中的 $k$ 个结点交换它们的 $b_i$,总代价为 $k \times a_{root}$ ,判断能否把所有结点都变为目标数字以及最小代价. 题解 因为每棵子树都可以被包含进更大的子树中,所以对于每棵子树的根节点,它的最小选取代…