6468: Snuke's Coloring

6468: Snuke's Coloring

时间限制: 2 Sec  内存限制: 128 MB
提交: 50  解决: 22
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题目描述

We have a grid with H rows and W columns. At first, all cells were painted white.
Snuke painted N of these cells. The i-th ( 1≤i≤N ) cell he painted is the cell at the ai-th row and bi-th column.
Compute the following:
For each integer j ( 0≤j≤9 ), how many subrectangles of size 3×3 of the grid contains exactly j black cells, after Snuke painted N cells?

Constraints
3≤H≤109
3≤W≤109
0≤N≤min(105,H×W)
1≤ai≤H (1≤i≤N)
1≤bi≤W (1≤i≤N)
(ai,bi)≠(aj,bj) (i≠j)

输入

The input is given from Standard Input in the following format:
H W N
a1 b1
:
aN bN

输出

Print 10 lines. The (j+1)-th ( 0≤j≤9 ) line should contain the number of the subrectangles of size 3×3 of the grid that contains exactly j black cells.

样例输入

4 5 8
1 1
1 4
1 5
2 3
3 1
3 2
3 4
4 4

样例输出

0
0
0
2
4
0
0
0
0
0

提示

There are six subrectangles of size 3×3. Two of them contain three black cells each, and the remaining four contain four black cells each.

来源

ABC045&ARC061 

题意：一个h*w的棋盘，涂黑n个格子，求含有0~9个黑格子的3*3的矩阵分别有多少个

思路：

h和w的数据范围是1e9  显然不能开二维矩阵存涂黑的格子。

每个黑格子只对周围九个3*3的矩阵有贡献，那么可以存一下左上角格子的坐标，然后统计一下就可以了。

#include <bits/stdc++.h>
using namespace std;
const int maxn=1e6+10,inf=1e9+7;
typedef long long ll;
ll h,w,node[maxn],n,a,b,cnt=0,zero,ans[15];

int main(){
    scanf("%lld%lld%lld",&h,&w,&n);
    zero=(h-2)*(w-2);
    while(n--){
        scanf("%lld%lld",&a,&b);
        for (int i=-2;i<=0;i++){
            for (int j=-2;j<=0;j++){
                if(a+i>=1 && a+i <=h-2 && b+j>=1 &&b+j <=w-2){
                    node[cnt++]=inf*(a+i)+(b+j);
                }
            }
        }
    }
    sort(node,node+cnt);
    for (int i=0,tmp=1;i<cnt;i++){
        if(node[i]==node[i+1]) tmp++;
        else ans[tmp]++,zero--,tmp=1;
    }
    printf("%lld
",zero);
    for (int i=1;i<10;i++)
        printf("%lld
",ans[i]);
    return 0;
}