10574 - Counting Rectangles 题目链接 题意:给定一些点,求可以成几个边平行于坐标轴的矩形 思路:先把点按x排序,再按y排序.然后用O(n^2)的方法找出每条垂直x轴的边,保存这些边两点的y坐标y1, y2.之后把这些边按y1排序,再按y2排序.用O(n)的方法找出有几个连续的y1, y2都相等.那么这些边两两是能构成矩形的.为C2cnt种.然后累加起来就是答案 代码: #include <stdio.h> #include <string.h> #inc…

Description Problem H Counting Rectangles Input: Standard Input Output:Standard Output Time Limit: 3Seconds   Given n points on the XY plane, count how many regular rectanglesare formed. A rectangle is regular if and only if its sides are all paralle…

Given n points on the XY plane, count how many regular rectangles are formed. A rectangle is regular if and only if its sides are all parallel to the axis.InputThe first line contains the number of tests t (1 ≤ t ≤ 10). Each case contains a single lin…

Counting Rectangles Time Limit: 1000MS Memory Limit: 10000K Total Submissions: 1043 Accepted: 546 Description We are given a figure consisting of only horizontal and vertical line segments. Our goal is to count the number of all different rectangles…

Counting rectangles By counting carefully it can be seen that a rectangular grid measuring 3 by 2 contains eighteen rectangles: Although there exists no rectangular grid that contains exactly two million rectangles, find the area of the grid with the…

D. Counting Rectangles is Fun time limit per test 4 seconds memory limit per test 256 megabytes input standard input output standard output There is an n × m rectangular grid, each cell of the grid contains a single integer: zero or one. Let's call t…

$ >Codeforces \space 372 B.  Counting Rectangles is Fun<$ 题目大意 : 给出一个 \(n \times m\) 的 \(01\) 矩阵,有 \(q\) 次询问,每次给出一个矩形 $ x_1, x_2, y_1, y_2$ ,求有多这个矩形的有多少个全 \(0\) 子矩形 \(1 \leq n, m \leq 50, 1 \leq q \leq 3 \times 10^5\) 解题思路 : 设 \(g(x, y, l, r)\) 表示以…

题目链接:uva 1436 - Counting heaps 题目大意:给出一个树的形状,如今为这棵树标号,保证根节点的标号值比子节点的标号值大,问有多少种标号树. 解题思路:和村名排队的思路是一仅仅的uva11174,最后问题仅仅和树德结构有直接关系.f(root)=(s(root)−1)!(s(1)∗s(2)∗⋯∗s(n) 可是给定的取模数不是质数.所以不能用逆元做.仅仅能将分子分母分别拆分成质因子,然后对质因子进制约分.由于最后的答案一定是正整数,所以对于每一个质因子,分子分解出的因子个数…

题目链接:12075 - Counting Triangles 题意:求n * m矩形内,最多能组成几个三角形 这题和UVA 1393类似,把总情况扣去三点共线情况,那么问题转化为求三点共线的情况,对于两点,求他们的gcd - 1,得到的就是他们之间有多少个点,那么情况数就能够求了,然后还是利用容斥原理去计数,然后累加出答案 代码: #include <stdio.h> #include <string.h> #include <algorithm> using nam…

Description We are given a figure consisting of only horizontal and vertical line segments. Our goal is to count the number of all different rectangles formed by these segments. As an example, the number of rectangles in the Figures 1 and 2 are 5 and…