Stars Time Limit: 5000/2000 MS (Java/Others) Memory Limit: 32768/65536 K (Java/Others) Total Submission(s): 785 Accepted Submission(s): 335 Problem Description Yifenfei is a romantic guy and he likes to count the stars in the sky. To make the p…
描述 Now I am leaving hust acm. In the past two and half years, I learned so many knowledge about Algorithm and Programming, and I met so many good friends. I want to say sorry to Mr, Yin, I must leave now ~~>.<~~. I am very sorry, we could not advanc…
http://acm.hdu.edu.cn/showproblem.php?pid=2642 题目大意:一个星空,二维的.上面有1000*1000的格点,每个格点上有星星在闪烁.一开始时星星全部暗淡着,有Q个操作: B x y 点亮一盏星星 D x y 熄灭一盏星星 Q fx tx fy ty 查询这个矩形里面亮着的星星的个数. 题解:首先,注意输入的x,y可能是(0,0),这样一来,用树状数组就不好维护了,所以将之平移一个单位,每当读入一对坐标,要进行x++,y++.. 其次,输入的查询,矩形…
题意:给你一个n*n的全0矩阵,每次有两个操作: C x1 y1 x2 y2:将(x1,y1)到(x2,y2)的矩阵全部值求反 Q x y:求出(x,y)位置的值 树状数组标准是求单点更新区间求和,但是我们处理一下就可以完美解决此问题.区间更新可以使用区间求和的方法,在更新的(x2,y2)记录+1,在更新的(x1-1,y1-1)-1(向前更新到最前方).单点求和就只需要与区间更新相反,向后求一个区间和.这样做的理由是:如果求和的点在某次更新范围内,我们+1但是不执行-1,否者要么都不执行,要么都…
Description Given an N*N matrix A, whose elements are either 0 or 1. A[i, j] means the number in the i-th row and j-th column. Initially we have A[i, j] = 0 (1 <= i, j <= N). We can change the matrix in the following way. Given a rectangle whose upp…
题目链接:http://poj.org/problem?id=1195 [题意] 给出一个全0的矩阵,然后一些操作 0 S:初始化矩阵,维数是S*S,值全为0,这个操作只有最开始出现一次 1 X Y A:对于矩阵的X,Y坐标增加A 2 L B R T:询问(L,B)到(R,T)区间内值的总和 3:结束对这个矩阵的操作 [思路] 二维树状数组单点更新+区域查询,可作为模板题. 注意坐标是从0开始,所以要+1 [代码] #include<cstdio> #include<cstrin…
Triple Time Limit: 12000/6000 MS (Java/Others) Memory Limit: 65536/65536 K (Java/Others)Total Submission(s): 388 Accepted Submission(s): 148 Problem Description Given the finite multi-set A of n pairs of integers, an another finite multi-set B …
题目链接 Problem Description Given the finite multi-set A of n pairs of integers, an another finite multi-set B of m triples of integers, we define the product of A and B as a multi-set C=A∗B={⟨a,c,d⟩∣⟨a,b⟩∈A, ⟨c,d,e⟩∈B and b=e} For each ⟨a,b,c⟩∈C, its B…
题目链接:[http://acm.split.hdu.edu.cn/showproblem.php?pid=5517] 题意:定义multi_set A<a , d>,B<c , d , e>,C<x , y , z>,给出 A , B ,定义 C = A * B = ={⟨a,c,d⟩∣⟨a,b⟩∈A, ⟨c,d,e⟩∈B and b=e} .求出C之后,求C中一个元素t[i]<a , b , c>是否存在一个元素tmp<x , y , z>使…
Given an N*N matrix A, whose elements are either 0 or 1. A[i, j] means the number in the i-th row and j-th column. Initially we have A[i, j] = 0 (1 <= i, j <= N). We can change the matrix in the following way. Given a rectangle whose upper-left corn…
D. Iahub and Xors Iahub does not like background stories, so he'll tell you exactly what this problem asks you for. You are given a matrix a with n rows and n columns. Initially, all values of the matrix are zeros. Both rows and columns are 1-based…
Matrix Time Limit: 3000MS Memory Limit: 65536K Total Submissions: 17224 Accepted: 6460 Description Given an N*N matrix A, whose elements are either 0 or 1. A[i, j] means the number in the i-th row and j-th column. Initially we have A[i, j] = 0 (1…
题目:http://poj.org/problem?id=2155 中文题意: 给你一个初始全部为0的n*n矩阵,有如下操作 1.C x1 y1 x2 y2 把矩形(x1,y1,x2,y2)上的数全部取反,1->0,0->1 2.Q x y 求n*n矩阵的(x,y)位置上的数 题解: 先看简单的: 给你一个初始全为0的长度为n的序列,有如下操作 1.C x y 把序列x到y位取反1->0,0->1 2.Q x 求序列第x位的数 做法很简单,设计一个数组a[],a[1..i]的和表示…
