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…
Mobile phones Time Limit: 5000MS   Memory Limit: 65536K Total Submissions: 16893   Accepted: 7789 Description Suppose that the fourth generation mobile phone base stations in the Tampere area operate as follows. The area is divided into squares. The…
树状数组支持两种操作: Add(x, d)操作:   让a[x]增加d. Query(L,R): 计算 a[L]+a[L+1]……a[R]. 当要频繁的对数组元素进行修改,同时又要频繁的查询数组内任一区间元素之和的时候,可以考虑使用树状数组. 通常对一维数组最直接的算法可以在O(1)时间内完成一次修改,但是需要O(n)时间来进行一次查询.而树状数组的修改和查询均可在O(log(n))的时间内完成. 在二维情况下:数组A[][]的树状数组定义为: C[x][y] = ∑ a[i][j], 其中, …
Description Suppose that the fourth generation mobile phone base stations in the Tampere area operate as follows. The area is divided into squares. The squares form an S * S matrix with the rows and columns numbered from 0 to S-1. Each square contain…
[题意]给你一个矩阵(初始化为0)和一些操作,1 x y a表示在arr[x][y]加上a,2 l b r t 表示求左上角为(l,b),右下角为(r,t)的矩阵的和. [思路]帮助更好理解树状数组. #include<iostream> #include<stdio.h> #include<string.h> using namespace std; ; int c[N][N]; int s; int lowbit(int x) { return x&(-x)…
http://poj.org/problem?id=1195 模版题 i写成k了 找了一个多小时没找出来.. #include <iostream> #include<cstring> #include<algorithm> #include<stdlib.h> #include<cstdio> using namespace std; #define N 1050 #define lowbit(x) (x&(-x)) int n,c[N…
#include<iostream> #include<cstdio> #include<cstring> #include<algorithm> using namespace std; int a[1300][1300]; int s; int lowbit(int x) { return x&(-x); } void add(int x,int y,int d) { for(int i=x;i<=s;i+=lowbit(i)) for(i…
Mobile phones Time Limit: 5000MS   Memory Limit: 65536K Total Submissions: 14489   Accepted: 6735 Description Suppose that the fourth generation mobile phone base stations in the Tampere area operate as follows. The area is divided into squares. The…
Description Suppose that the fourth generation mobile phone base stations in the Tampere area operate as follows. The area is divided into squares. The squares form an S * S matrix with the rows and columns numbered from 0 to S-1. Each square contain…
Description Suppose that the fourth generation mobile phone base stations in the Tampere area operate as follows. The area is divided into squares. The squares form an S * S matrix with the rows and columns numbered from 0 to S-1. Each square contain…