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 <= i, j <= N).
We can change the matrix in the following way. Given a rectangle whose upper-left corner is (x1, y1) and lower-right corner is (x2, y2), we change all the elements in the rectangle by using “not” operation (if it is a ‘0’ then change it into ‘1’ otherwise change it into ‘0’). To maintain the information of the matrix, you are asked to write a program to receive and execute two kinds of instructions.
1. C x1 y1 x2 y2 (1 <= x1 <= x2 <= n, 1 <= y1 <= y2 <= n) changes the matrix by using the rectangle whose upper-left corner is (x1, y1) and lower-right corner is (x2, y2).
2. Q x y (1 <= x, y <= n) querys A[x, y].
Input
The first line of the input is an integer X (X <= 10) representing the number of test cases. The following X blocks each represents a test case.
The first line of each block contains two numbers N and T (2 <= N <= 1000, 1 <= T <= 50000) representing the size of the matrix and the number of the instructions. The following T lines each represents an instruction having the format “Q x y” or “C x1 y1 x2 y2”, which has been described above.
Output
For each querying output one line, which has an integer representing A[x, y].
There is a blank line between every two continuous test cases.
Sample Input
1 2 10 C 2 1 2 2 Q 2 2 C 2 1 2 1 Q 1 1 C 1 1 2 1 C 1 2 1 2 C 1 1 2 2 Q 1 1 C 1 1 2 1 Q 2 1
Sample Output
1 0 0 1
Source
POJ Monthly,Lou Tiancheng
这题二维线段树也可以做。
二维线段树需要 给一个矩形加一个值
查询单个的值。
加值的时候直接加一个块。
查询的时候把这个点以及和这个点相关的都累加起来。
数据结构写法多样啊,重在理解
1 /* *********************************************** 2 Author :kuangbin 3 Created Time :2014/5/23 23:08:19 4 File Name :E:\2014ACM\专题学习\数据结构\二维线段树\POJ2155.cpp 5 ************************************************ */ 6 7 #include <stdio.h> 8 #include <string.h> 9 #include <iostream> 10 #include <algorithm> 11 #include <vector> 12 #include <queue> 13 #include <set> 14 #include <map> 15 #include <string> 16 #include <math.h> 17 #include <stdlib.h> 18 #include <time.h> 19 using namespace std; 20 const int MAXN = 1010; 21 struct Nodey 22 { 23 int l,r; 24 int val; 25 }; 26 int n; 27 int locx[MAXN],locy[MAXN]; 28 struct Nodex 29 { 30 int l,r; 31 Nodey sty[MAXN*3]; 32 void build(int i,int _l,int _r) 33 { 34 sty[i].l = _l; 35 sty[i].r = _r; 36 sty[i].val = 0; 37 if(_l == _r) 38 { 39 locy[_l] = i; 40 return; 41 } 42 int mid = (_l + _r)>>1; 43 build(i<<1,_l,mid); 44 build((i<<1)|1,mid+1,_r); 45 } 46 void add(int i,int _l,int _r,int val) 47 { 48 if(sty[i].l == _l && sty[i].r == _r) 49 { 50 sty[i].val += val; 51 return; 52 } 53 int mid = (sty[i].l + sty[i].r)>>1; 54 if(_r <= mid)add(i<<1,_l,_r,val); 55 else if(_l > mid)add((i<<1)|1,_l,_r,val); 56 else 57 { 58 add(i<<1,_l,mid,val); 59 add((i<<1)|1,mid+1,_r,val); 60 } 61 } 62 }stx[MAXN*3]; 63 void build(int i,int l,int r) 64 { 65 stx[i].l = l; 66 stx[i].r = r; 67 stx[i].build(1,1,n); 68 if(l == r) 69 { 70 locx[l] = i; 71 return; 72 } 73 int mid = (l+r)>>1; 74 build(i<<1,l,mid); 75 build((i<<1)|1,mid+1,r); 76 } 77 void add(int i,int x1,int x2,int y1,int y2,int val) 78 { 79 if(stx[i].l == x1 && stx[i].r == x2) 80 { 81 stx[i].add(1,y1,y2,val); 82 return; 83 } 84 int mid = (stx[i].l + stx[i].r)/2; 85 if(x2 <= mid)add(i<<1,x1,x2,y1,y2,val); 86 else if(x1 > mid)add((i<<1)|1,x1,x2,y1,y2,val); 87 else 88 { 89 add(i<<1,x1,mid,y1,y2,val); 90 add((i<<1)|1,mid+1,x2,y1,y2,val); 91 } 92 } 93 int sum(int x,int y) 94 { 95 int ret = 0; 96 for(int i = locx[x];i;i >>= 1) 97 for(int j = locy[y];j;j >>= 1) 98 ret += stx[i].sty[j].val; 99 return ret; 100 } 101 102 int main() 103 { 104 //freopen("in.txt","r",stdin); 105 //freopen("out.txt","w",stdout); 106 int T; 107 scanf("%d",&T); 108 while(T--) 109 { 110 int q; 111 scanf("%d%d",&n,&q); 112 build(1,1,n); 113 char op[10]; 114 int x1,x2,y1,y2; 115 while(q--) 116 { 117 scanf("%s",op); 118 if(op[0] == 'C') 119 { 120 scanf("%d%d%d%d",&x1,&y1,&x2,&y2); 121 add(1,x1,x2,y1,y2,1); 122 } 123 else 124 { 125 scanf("%d%d",&x1,&y1); 126 if(sum(x1,y1)%2 == 0)printf("0\n"); 127 else printf("1\n"); 128 } 129 } 130 if(T)printf("\n"); 131 } 132 return 0; 133 }