2820: I-country
Description
在 N*M 的矩阵中,每个格子有一个权值,要求寻找一个包含 K 个格子的凸连通块(连通块中间没有空缺,并且轮廓是凸的,如书中图片所示),使这个连通块中的格子的权值和最大。求出这个最大的权值和,并给出连通块的具体方案。本题有SPJ,输出任意一种方案即可。N,M≤15,K≤225。
According to top-secret A-country plans, I-country is divided into N*M equal squares, each square contains some oil resources. They want to occupy all the territory of I-country, but the UN (United Nations) will allow them to occupy only K squares. Of course, A-country want to get control over as many oil as possible, but, they will have to guard all their territory. So, they need their territory to be easy-controlled, i.e. from any square to any it must be possible to get moving only along two directions (selected from the next list: left, right, up, down; for different squares pairs of directions may differ).
You are to write a program, which determinies, what squares will be occupyed by A-country. If there are several solutions, you may output any.
Input
Output
Sample Input Copy
2 3 4
10 20 30
40 2 3
Sample Output Copy
Oil : 100
1 1
1 2
1 3
2 1