Zhuge Liang‘s Mines
Time Limit: 2000/1000 MS (Java/Others) Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 1318 Accepted Submission(s): 557
Problem Description
In the ancient three kingdom period, Zhuge Liang was the most famous and smartest military leader. His enemy was Shima Yi, who always looked stupid when fighting against Zhuge Liang. But it was Shima Yi who laughed to the end.
Once, Zhuge Liang sent the arrogant Ma Shu to defend Jie Ting, a very important fortress. Because Ma Shu is the son of Zhuge Liang‘s good friend Ma liang, even Liu Bei, the Ex. king, had warned Zhuge Liang that Ma Shu was always bragging and couldn‘t be used,
Zhuge Liang wouldn‘t listen. Shima Yi defeated Ma Shu and took Jie Ting. Zhuge Liang had to kill Ma Shu and retreated. To avoid Shima Yi‘s chasing, Zhuge Liang put some mines on the only road. Zhuge Liang deployed the mines in a Bagua pattern which made the
mines very hard to remove. If you try to remove a single mine, no matter what you do ,it will explode. Ma Shu‘s son betrayed Zhuge Liang , he found Shima Yi, and told Shima Yi the only way to remove the mines: If you remove four mines which form the four vertexes
of a square at the same time, the removal will be success. In fact, Shima Yi was not stupid. He removed as many mines as possible. Can you figure out how many mines he removed at that time?
The mine field can be considered as a the Cartesian coordinate system. Every mine had its coordinates. To simplify the problem, please only consider the squares which are parallel to the coordinate axes.
Input
There are no more than 15 test cases.
In each test case:
The first line is an integer N, meaning that there are N mines( 0 < N <= 20 ).
Next N lines describes the coordinates of N mines. Each line contains two integers X and Y, meaning that there is a mine at position (X,Y). ( 0 <= X,Y <= 100)
The input ends with N = -1.
Output
For each test case ,print the maximum number of mines Shima Yi removed in a line.
Sample Input
3 1 1 0 0 2 2 8 0 0 1 0 2 0 0 1 1 1 2 1 10 1 10 0 -1
Sample Output
0 4
题意：平面上给出n<=20个点，求出这些点能构成最多的正方形数量，用过的点不能再用
思路：看到n<=20果断想到状压DP了，但是直接在每种状态里枚举满足的正方形方案果断会超时，所以要先预处理
可以预处理出所有满足的正方形，这些正方形的数量大概不会超过几百个
然后就状态DP直接操了，很简单的转移，就不多说了