题目链接 POJ2155 题解 二维线段树水题,蒟蒻本想拿来养生一下 数据结构真的是有毒啊,, TM这题卡常 动态开点线段树会TLE[也不知道为什么] 直接开个二维数组反倒能过 #include<algorithm> #include<iostream> #include<cstring> #include<cstdio> #include<cmath> #include<map> #define Redge(u) for (int…

poj2155 题意 二维区间更新,单点查询. 分析 二维线段树. 也可以用二维树状数组去做,维护矩阵前缀和. code #include<cstdio> using namespace std; typedef long long ll; #define lson l, m, rt << 1 #define rson m + 1, r, rt << 1 | 1 const int MAXN = 4001; int n, val[MAXN][MAXN]; int x,…

题目链接: https://vjudge.net/problem/POJ-2155 题目大意: 给一个n*n的01矩阵,然后有两种操作(m次)C x1 y1 x2 y2是把这个小矩形内所有数字异或一遍,Q x y 是询问当前这个点的值是多少?n<=1000 m<=50000. 解题思路: 裸的二维树状数组,但是这里是区域更新,单点查询, 做法应该是 #include<cstdio> #include<cstring> #include<iostream> #…

题目链接 二维树状数组 #include<iostream> #include<math.h> #include<algorithm> #include<stdlib.h> using namespace std; #define ll long long #define re(i,n) for(int i=0;i<n;i++) ; int c[maxn][maxn]; int n, q; int lowbit(int x){ return x&…

Matrix Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 25004   Accepted: 9261 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…

Matrix Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 14826   Accepted: 5583 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…

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…

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 up…

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…