2064. Bookshelf 2

单点时限: 2.0 sec

内存限制: 256 MB

Farmer John recently bought another bookshelf for the cow library,but the shelf is getting filled up quite quickly, and now the only available space is at the top.

FJ has N cows (1 <= N <= 20) each with some height of H_i (1 <= H_i <= 1,000,000 - these are very tall cows). The bookshelf has a height of B (1 <= B <= S, where S is the sum of the heights of all cows).

To reach the top of the bookshelf, one or more of the cows can stand on top of each other in a stack, so that their total height is the sum of each of their individual heights. This total height must be no less than the height of the bookshelf in order for the cows to

reach the top.

Since a taller stack of cows than necessary can be dangerous, your job is to find the set of cows that produces a stack of the smallest height possible such that the stack can reach the bookshelf. Your program should print the minimal ‘excess’ height between the optimal

stack of cows and the bookshelf.

输入格式

  • Line 1: Two space-separated integers: N and B

  • Lines 2..N+1: Line i+1 contains a single integer: H_i

输出格式

  • Line 1: A single integer representing the (non-negative) difference between the total height of the optimal set of cows and the height of the shelf.

样例

Input
5 16
3
1
3
5
6
Output
1
OUTPUT DETAILS:
Here we use cows 1, 3, 4, and 5, for a total height of 3 + 3 + 5 + 6 = 17.It is not possible to obtain a total height of 16, so the answer is 1.

53 人解决,70 人已尝试。

69 份提交通过,共有 143 份提交。

3.7 EMB 奖励。

创建: 12 年,7 月前.

修改: 2 年,11 月前.

最后提交: 3 月,2 周前.

来源: USACO

题目标签
DP