- Time limit: 1.00 s
- Memory limit: 512 MB
You are given a tree consisting of n nodes.
A matching is a set of edges where each node is an endpoint of at most one edge. What is the maximum number of edges in a matching?
The first input line contains an integer n: the number of nodes. The nodes are numbered 1,2,\ldots,n.
Then there are n-1 lines describing the edges. Each line contains two integers a and b: there is an edge between nodes a and b.
Print one integer: the maximum number of pairs.
- 1 \le n \le 2 \cdot 10^5
- 1 \le a,b \le n
5 1 2 1 3 3 4 3 5
Explanation: One possible matching is (1,2) and (3,4).