http://poj.org/problem?id=2155 Matrix Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 18143   Accepted: 6813 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. I…

Matrix Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 20599   Accepted: 7673 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…

题意:给你一个矩阵开始全是0,然后给你两种指令,第一种:C x1,y1,x2,y2 就是将左上角为x1,y1,右下角为x2,y2,的这个矩阵内的数字全部翻转,0变1,1变0 第二种:Q x1 y1,输出举证x1,y1,位置的数值 思路:该题的巧妙之处是反转的重叠抵消,记住要向上统计,向下修改:二维情况,最主要的是理解那个数组中的每个点保存的值的意义(一个矩形区域的总和):最后记住取余: 此题参考博客 http://blog.csdn.net/xymscau/article/details/660…

题目链接[http://poj.org/problem?id=2155] /* poj 2155 Matrix 题意:矩阵加减,单点求和 二维线段树,矩阵加减,单点求和. */ using namespace std; const int INF = 0x3f3f3f3f; ; int N, Q; struct Nodey { int l, r; int val; }; int locx[MAXN], locy[MAXN]; struct Nodex { int l, r; Nodey sty[…

题目链接:http://poj.org/problem?id=2155 Matrix Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 32950   Accepted: 11943 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 col…

Matrix Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 17880   Accepted: 6709 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…

Matrix Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 17226   Accepted: 6461 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…

Matrix Time Limit: 3000MS   Memory Limit: 65536K Total Submissions: 16797   Accepted: 6312 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…

[题目链接] http://poj.org/problem?id=2155 [题目大意] 要求维护两个操作,矩阵翻转和单点查询 [题解] 树状数组可以处理前缀和问题,前缀之间进行容斥即可得到答案. [代码] #include <cstring> #include <cstdio> const int N=1010; using namespace std; int c[N][N],n,m,T; char op[2]; void add(int x,int y){ int i,j,k…

附一篇经典翻译,学习 树状数组  http://www.hawstein.com/posts/binary-indexed-trees.html /** * @author johnsondu * @time 2015-8-22 * @type 2D Binary Index Tree * @strategy 如果翻转的是(x1,y1), (x2,y2)区域.则相当于 * 翻转(0, 0)~(x2, y2), 然后再翻转(0,0)~(x1-1, y2) * (0, 0)~(x2, y1-1),…