[Link] https://www.acmicpc.net/problem/1949
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import java.util.*;
import java.io.*;
public class Main {
static BufferedReader br;
static StringBuilder sb = new StringBuilder();
static int[] fdp;
static int[] edp;
static boolean[] visit;
public static void main(String[] args) throws IOException {
br = new BufferedReader(new InputStreamReader(System.in));
int n = toi(br.readLine());
int[] arr;
Node[] nodes = new Node[n];
fdp = new int[n];
edp = new int[n];
Arrays.fill(fdp, 1);
visit = new boolean[n];
for(int i = 0; i < n; i++) nodes[i] = new Node(i);
for(int i = 0; i < n - 1; i++) {
arr = getArr();
int a = arr[0] - 1, b = arr[1] - 1;
nodes[a].list.add(nodes[b]);
nodes[b].list.add(nodes[a]);
}
nodes[0].parent = -1;
bfs(nodes[0]);
int ans = 0;
println(edp[0] == 0 ? fdp[0] : Math.min(edp[0], fdp[0]));
}
static void bfs(Node node) {
if(node.list.size() == 1 && node.parent != -1) {
return;
}
for(Node child: node.list) {
if(child.idx == node.parent) continue;
child.parent = node.idx;
if(!visit[child.idx]) bfs(child);
fdp[node.idx] += Math.min(fdp[child.idx], edp[child.idx]);
edp[node.idx] += fdp[child.idx];
}
visit[node.idx] = true;
}
static class Node {
int idx;
int parent;
boolean evenIdx = false;
ArrayList<Node> list = new ArrayList<>();
Node(int idx) { this.idx = idx; }
}
static int toi(String s) { return Integer.parseInt(s); }
static String[] getLine() throws IOException { return br.readLine().split(" "); }
static int[] getArr() throws IOException { return Arrays.stream(br.readLine().split(" ")).mapToInt(Integer::parseInt).toArray(); }
static <T> void print(T s) { System.out.print(s); }
static <T> void println(T s) { System.out.println(s); }
}