先上题目：
Chopsticks
Time Limit: 2000/1000 MS
(Java/Others) Memory Limit: 65536/32768 K
(Java/Others)
Total Submission(s): 1538 Accepted
Submission(s): 715
Problem Description
In China, people use a pair of chopsticks to get food
on the table, but Mr. L is a bit different. He uses a set of three chopsticks --
one pair, plus an EXTRA long chopstick to get some big food by piercing it
through the food. As you may guess, the length of the two shorter chopsticks
should be as close as possible, but the length of the extra one is not
important, as long as it‘s the longest. To make things clearer, for the set of
chopsticks with lengths A,B,C(A<=B<=C), (A-B)^2 is called the ‘badness‘ of
the set.
It‘s December 2nd, Mr.L‘s birthday! He invited K people to
join his birthday party, and would like to introduce his way of using
chopsticks. So, he should prepare K+8 sets of chopsticks(for himself, his wife,
his little son, little daughter, his mother, father, mother-in-law,
father-in-law, and K other guests). But Mr.L suddenly discovered that his
chopsticks are of quite different lengths! He should find a way of composing the
K+8 sets, so that the total badness of all the sets is minimized.
Input
The first line in the input contains a single integer
T, indicating the number of test cases(1<=T<=20). Each test case begins
with two integers K, N(0<=K<=1000, 3K+24<=N<=5000), the number of
guests and the number of chopsticks. There are N positive integers Li on the
next line in non-decreasing order indicating the lengths of the
chopsticks.(1<=Li<=32000).
Output
For each test case in the input, print a line
containing the minimal total badness of all the sets.
Sample Input
1
1 40
1 8 10 16 19 22 27 33 36 40 47 52 56 61 63 71 72 75 81 81 84 88 96 98 103
110 113 118 124 128 129 134 134 139 148 157 157 160 162 164
Sample Output
23
Note For the sample input, a possible collection of the 9 sets is: 8,10,16;
19,22,27; 61,63,75; 71,72,88; 81,81,84; 96,98,103; 128,129,148; 134,134,139;
157,157,160
题意：主角有特别的用筷子技巧→_→，喜欢有两个短的且两者的长度差值最小且配上一根长的，现在告诉你需要从n根筷子里面挑k+8组筷子，问你总的每一组短的筷子的长度差值最小。
跟HDU的1421相似，不过这里需要再挑一根长的，这是一个限制条件，所以这里需要从大到小排序，排序完毕，因为我们需要先找到最长的那根筷子。
这一题还不能完全地理解，需要再想一下。
在其他人的博客上面看的分析不是很懂···看来DP还要加强啊。
HDU - 1500 - Chopsticks,布布扣,bubuko.com
HDU - 1500 - Chopsticks
原文：http://www.cnblogs.com/sineatos/p/3575164.html
