题 There are n sharks who grow flowers for Wet Shark. They are all sitting around the table, such that sharks i andi + 1 are neighbours for all i from 1 to n - 1. Sharks n and 1 are neighbours too. Each shark will grow some number of flowers si. For i…

time limit per test2 seconds memory limit per test256 megabytes inputstandard input outputstandard output There are b blocks of digits. Each one consisting of the same n digits, which are given to you in the input. Wet Shark must choose exactly one d…

题 Today, Wet Shark is given n integers. Using any of these integers no more than once, Wet Shark wants to get maximum possible even (divisible by 2) sum. Please, calculate this value for Wet Shark. Note, that if Wet Shark uses no integers from the n …

题 题意 1000*1000的格子里,给你n≤200 000个点的坐标,求有多少对在一个对角线上. 分析 如果求每个点有几个共对角线的点,会超时. 考虑到对角线总共就主对角线1999条+副对角线1999条,我们可以求每个对角线有几对点. 同一条主对角线上的元素有a[i]个,就有C(a[i],2)对点: 同一条副对角线上的元素有b[i]个,就有C(b[i],2)对点. 读入x和y后, x+y相同的就在同一副对角线,x+y范围是(2,2000), x-y相同的就是同一主对角线,x-y范围是(-999…

[codeforces 415D]Mashmokh and ACM 题意:美丽数列定义:对于数列中的每一个i都满足:arr[i+1]%arr[i]==0 输入n,k(1<=n,k<=2000),问满足[数列长度是k && 数列中每一个元素arr[i]在1~n之间 && 数列中元素可以重复]的数列有多少个?结果对10^9+7取余 解题思路:dp[i][j]表示长度是j,最后一位是i的种数 if(kk%i==0) dp[kk][j+1]+=dp[i][j] #inc…

C. Wet Shark and Flowers time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output There are n sharks who grow flowers for Wet Shark. They are all sitting around the table, such that sharks i and i …

time limit per test2 seconds memory limit per test256 megabytes inputstandard input outputstandard output Little Alyona is celebrating Happy Birthday! Her mother has an array of n flowers. Each flower has some mood, the mood of i-th flower is ai. The…

[题目链接] http://codeforces.com/contest/451/problem/E [算法] 容斥原理 [代码] #include<bits/stdc++.h> using namespace std; typedef long long ll; ; int i,j,n,s,ans,MASK; ll m,t; ll a[],f[]; ]; inline int power(int a,int n) { ,b = a; while (n) { ) res = 1ll * res…

time limit per test2 seconds memory limit per test256 megabytes inputstandard input outputstandard output Wet Shark asked Rat Kwesh to generate three positive real numbers x, y and z, from 0.1 to 200.0, inclusive. Wet Krash wants to impress Wet Shark…

[题目链接]:http://codeforces.com/contest/707/problem/E [题意] 给你一个n*m的方阵; 里面有k个联通块; 这k个联通块,每个连通块里面都是灯; 给你q个操作; 有以下两种类型 ①将第i个连通块里面灯取反 ②询问你(x1,y1)(x2,y2)这个矩形区域内灯的权值的和; [题解] 要用到二维的树状数组; 取反操作只要O(1)就能完成; 即先不管它是什么,取反就是了; 然后在询问的时候,直接用二维树状数组累加; 这里的累加可能是减也可能是加; 也可能…