51nod p1007 将一堆正整数分为2组，要求2组的和相差最小。 例如：1 2 3 4 5，将1 2 4分为1组，3 5分为1组，两组和相差1，是所有方案中相差最少的。

As Harry Potter series is over, Harry has no job. Since he wants to make quick money, (he wants everything qui…

Description A straight dirt road connects two fields on FJ‘s farm, but it changes elevation more than FJ would…

传送门：Brackets 题意：（）与[ ]括号匹配，求有效匹配个数。 解法：简单区间DP

传送门：【HDU5501】The Highest Mark 分析：贪心+01背包 贪心求解做题顺序，动态规划求解做哪个题。

传送门：Codeforces Lavrenty, a baker, is going to make several buns with stuffings and sell them.

Problem Description 给你一个n*n的格子的棋盘，每个格子里面有一个非负数。 从中取出若干个数，使得任意的两个数所在的格子没有公共边，就是说所取的数所在的2个格子不能相邻，并且取出的数的和最大。 Inp…