#icpc2012autumnc. [icpc2012autumn_c]Median Tree
[icpc2012autumn_c]Median Tree
Problem Statement
You are given a connected undirected graph which has even numbers of nodes. A connected graph is a graph in which all nodes are connected directly or indirectly by edges.
Your task is to find a spanning tree whose median value of edges' costs is minimum. A spanning tree of a graph means that a tree which contains all nodes of the graph.
Input
The input consists of multiple datasets.
The format of each dataset is as follows.
...
The first line contains an even number () and an integer . is the nubmer of nodes and is the number of edges in the graph.
Then lines follow, each of which contains (), () and (). This means there is an edge between the nodes and and its cost is . There is no more than one edge which connects and .
The input terminates when and . Your program must not output anything for this case.
Output
Print the median value in a line for each dataset.
Sample Input
Sorry, update sample3 dataset.(11:33)```plain
2 1 1 2 5 4 6 1 2 1 1 3 2 1 4 3 2 3 4 2 4 5 3 4 6 8 17 1 4 767 3 1 609 8 3 426 6 5 972 8 1 607 6 4 51 5 1 683 3 6 451 3 4 630 8 7 912 3 7 43 4 7 421 3 5 582 8 4 538 5 7 832 1 6 345 8 2 608 0 0
### Output for the Sample Input
```plain
5
2
421
Source Name
JAG Practice Contest for ACM-ICPC Asia Regional 2012