hdu 5534 Partial Tree(完全背包)

 

Problem Description

In mathematics, and more specifically in graph theory, a tree is an undirected graph in which any two nodes are connected by exactly one path. In other words, any connected graph without simple cycles is a tree.

You find a partial tree on the way home. This tree has n nodes but lacks of n−1 edges. You want to complete this tree by adding n−1 edges. There must be exactly one path between any two nodes after adding. As you know, there are nn−2 ways to complete this tree, and you want to make the completed tree as cool as possible. The coolness of a tree is the sum of coolness of its nodes. The coolness of a node is f(d), where f is a predefined function and d is the degree of this node. What's the maximum coolness of the completed tree?

 

 

 

Input

The first line contains an integer T indicating the total number of test cases.
Each test case starts with an integer n in one line,
then one line with n−1 integers f(1),f(2),…,f(n−1).

1≤T≤2015
2≤n≤2015
0≤f(i)≤10000
There are at most 10 test cases with n>100.

 

 

 

Output

For each test case, please output the maximum coolness of the completed tree in one line.

 

 

 

Sample Input

2
3
2 1
4
5 1 4

 

 

Sample Output

5 
19

 

 

 

Source

2015ACM/ICPC亚洲区长春站-重现赛（感谢东北师大）

 

注意到一个节点数为n的树的度数和为2*n-2,所以问题就转换为了把2*n-2个度分配给n个节点所能获得的最大价值，而且每一个节点至少分到1个度。我们可以先每一个分一个度，然后把n-2个节点任意分配完。分配的时候因为已经分了1个度了，所以要把2~n-1的度看为1~n-1，然后做个完全背包就行了。

 1 #pragma comment(linker, "/STACK:1024000000,1024000000")
 2 #include
 3 #include
 4 #include
 5 #include
 6 #include
 7 #include
 8 #include
 9 #include<set>
10 #include
11 #include

View Code

 

转载于:https://www.cnblogs.com/UniqueColor/p/5001692.html