Description:
William really likes puzzle kits. For one of his birthdays, his friends gifted him a complete undirected edge-weighted graph consisting of $$$n$$$ vertices.
He wants to build a spanning tree of this graph, such that for the first $$$k$$$ vertices the following condition is satisfied: the degree of a vertex with index $$$i$$$ does not exceed $$$d_i$$$. Vertices from $$$k + 1$$$ to $$$n$$$ may have any degree.
William wants you to find the minimum weight of a spanning tree that satisfies all the conditions.
A spanning tree is a subset of edges of a graph that forms a tree on all $$$n$$$ vertices of the graph. The weight of a spanning tree is defined as the sum of weights of all the edges included in a spanning tree.
Input Format:
The first line of input contains two integers $$$n$$$, $$$k$$$ ($$$2 \leq n \leq 50$$$, $$$1 \leq k \leq min(n - 1, 5)$$$).
The second line contains $$$k$$$ integers $$$d_1, d_2, \ldots, d_k$$$ ($$$1 \leq d_i \leq n$$$).
The $$$i$$$-th of the next $$$n - 1$$$ lines contains $$$n - i$$$ integers $$$w_{i,i+1}, w_{i,i+2}, \ldots, w_{i,n}$$$ ($$$1 \leq w_{i,j} \leq 100$$$): weights of edges $$$(i,i+1),(i,i+2),\ldots,(i,n)$$$.
Output Format:
Print one integer: the minimum weight of a spanning tree under given degree constraints for the first $$$k$$$ vertices.
Note:
None