You are given an undirected1 tree with each of its nodes assigned a magic .
The magic of a path2 is defined as the product of the magic of the nodes on that path divided by the number of the nodes on the path. For example, the magic of a path that consists of nodes with magic and is .
In the given tree, find the path with the minimal magic and output the magic of that path.
Input Specification
The first line of input contains the integer , the number of nodes in the tree.
Each of the following lines contains two integers, and , the labels of nodes connected with an edge.
The of the following lines contains the integer , magic of the node.
Output Specification
Output the magic of the path with minimal magic in the form of a completely reduced fraction ( and are relatively prime integers).
In all test cases, it will hold that the required and are smaller than .
Scoring
In test cases worth 3 points total, it will hold .
In test cases worth 4.5 additional points total, there will not be a node that is connected to more than other nodes.
Sample Input 1
2
1 2
3
4
Sample Output 1
3/1
Explanation for Sample Output 1
Notice that the path may begin and end in the same node. The path with the minimal magic consists of the node with magic , so the entire path's magic is .
Sample Input 2
5
1 2
2 4
1 3
5 2
2
1
1
1
3
Sample Output 2
1/2
Explanation for Sample Output 2
The path that consists of nodes with labels and is of magic .
That is also the path with the minimal possible magic.
1An undirected tree is a connected graph that consists of nodes and undirected edges.
2A path in a graph is a finite sequence of edges which connect a sequence of vertices which are all distinct from one another.
Comments