传送门 Description Chloe, the same as Vladik, is a competitive programmer. She didn't have any problems to get to the olympiad like Vladik, but she was confused by the task proposed on the olympiad. Let's consider the following algorithm of generating a…
A. Petya and Origami Water. #include <bits/stdc++.h> using namespace std; #define ll long long ll n, k; ll Get(ll x) { ? (x * n) / k : (x * n) / k + ; } int main() { while (scanf("%lld%lld", &n, &k) != EOF) { ll res = Get() + Get()…
C. Plus and Square Root time limit per test 2 seconds memory limit per test 256 megabytes input standard input output standard output ZS the Coder is playing a game. There is a number displayed on the screen and there are two buttons, ' + ' (plus) an…
A. Black Square time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Quite recently, a very smart student named Jury decided that lectures are boring, so he downloaded a game called "Black Squar…
https://codeforces.com/contest/1080/problem/F 题意 有k个区间,区间的种类有n种,有m个询问(n,m<=1e5,k<=3e5),每次询问a,b,x,y,代表对于种类编号为[a,b]的每一种区间,是否都存在一个区间x<=l,r<=y,输出yes or no 思路 现将区间按左端点从小到大排序,对于每一个询问首先找出第一个左端点大于x的区间,然后看[a,b]中最大的右端点是否>y即可 需要一颗以种类编号为下标,右端点为权值的主席树,维…
C. Masha and two friends time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output Recently, Masha was presented with a chessboard with a height of nn and a width of mm. The rows on the chessboard ar…
B. Margarite and the best present 题目链接:https://codeforces.com/contest/1080/problem/B 题意: 给出一个数列:an=(-1)n,之后有询问,问 [l,r] 之间的ai和为多少. 题解:这个分情况讨论一下就可以了,区间长度的奇偶数丶左端点的奇偶数. 代码如下: #include <cstdio> #include <cstring> #include <algorithm> #include…
Ujan decided to make a new wooden roof for the house. He has nn rectangular planks numbered from 11 to nn. The ii-th plank has size ai×1ai×1 (that is, the width is 11 and the height is aiai). Now, Ujan wants to make a square roof. He will first choos…
A. Petya and Origamitime limit per test1 secondmemory limit per test256 megabytesinputstandard inputoutputstandard outputPetya is having a party soon, and he has decided to invite his n friends. He wants to make invitations in the form of origami. Fo…
C. Masha and two friends 题目链接:https://codeforc.es/contest/1080/problem/C 题意: 给出一个黑白相间的n*m的矩阵,现在先对一个子矩阵颜色变为白色,然后再对一个子矩阵颜色变为黑色,问最终白色格子和黑色格子有多少? 题解: 定义w(a,b)为(1,1)到(a,b)中白色的数量,通过观察找规律可以发现w(a,b)=((b+1)/2)*((a+1)/2)+(b/2)*(a/2). 然后b(a,b)就是格子总数量减去w(a,b). 现…
