Staircases
题意翻译
给定一个n*m的网格,每个格子为黑色或白色,初始时所有格子均为白色。
定义满足如下条件的路径为楼梯:
* 起点和终点均为白色
* 路径上的所有点均为白色
* 满足以下两种结构之一
1.第二个格子在第一个格子右面,第三个格子在第二个格子下面,第四个格子在第三个格子右面,以此类推……
2.第二个格子在第一个格子下面,第三个格子在第二个格子右面,第四个格子在第三个格子下面,以此类推……
此外,一个单独的白色格子也被视为一个楼梯。
给定q个询问,每个询问给定整数x、y,并将格子(x,y)颜色翻转。
输出每次操作后网格中不同楼梯的个数(操作不独立)。
题目描述
You are given a matrix, consisting of $ n $ rows and $ m $ columns. The rows are numbered top to bottom, the columns are numbered left to right.
Each cell of the matrix can be either free or locked.
Let's call a path in the matrix a staircase if it:
- starts and ends in the free cell;
- visits only free cells;
- has one of the two following structures:
1. the second cell is $ 1 $ to the right from the first one, the third cell is $ 1 $ to the bottom from the second one, the fourth cell is $ 1 $ to the right from the third one, and so on;
2. the second cell is $ 1 $ to the bottom from the first one, the third cell is $ 1 $ to the right from the second one, the fourth cell is $ 1 $ to the bottom from the third one, and so on.
In particular, a path, consisting of a single cell, is considered to be a staircase.
Here are some examples of staircases:
![](https://cdn.luogu.com.cn/upload/vjudge_pic/CF1598E/30e6b70a090f9657a06b957e8113944b3c2b16f3.png)Initially all the cells of the matrix are free.
You have to process $ q $ queries, each of them flips the state of a single cell. So, if a cell is currently free, it makes it locked, and if a cell is currently locked, it makes it free.
Print the number of different staircases after each query. Two staircases are considered different if there exists such a cell that appears in one path and doesn't appear in the other path.
输入输出格式
输入格式
The first line contains three integers $ n $ , $ m $ and $ q $ ( $ 1 \le n, m \le 1000 $ ; $ 1 \le q \le 10^4 $ ) — the sizes of the matrix and the number of queries.
Each of the next $ q $ lines contains two integers $ x $ and $ y $ ( $ 1 \le x \le n $ ; $ 1 \le y \le m $ ) — the description of each query.
输出格式
Print $ q $ integers — the $ i $ -th value should be equal to the number of different staircases after $ i $ queries. Two staircases are considered different if there exists such a cell that appears in one path and doesn't appear in the other path.
输入输出样例
输入样例 #1
2 2 8
1 1
1 1
1 1
2 2
1 1
1 2
2 1
1 1
输出样例 #1
5
10
5
2
5
3
1
0
输入样例 #2
3 4 10
1 4
1 2
2 3
1 2
2 3
3 2
1 3
3 4
1 3
3 1
输出样例 #2
49
35
24
29
49
39
31
23
29
27
输入样例 #3
1000 1000 2
239 634
239 634
输出样例 #3
1332632508
1333333000