[Link] https://www.acmicpc.net/problem/11725
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import java.util.*;
import java.io.*;
public class Main {
static BufferedReader br;
public static void main(String[] args) throws IOException {
br = new BufferedReader(new InputStreamReader(System.in));
String[] line;
StringBuilder sb = new StringBuilder();
int n = toi(br.readLine());
int[] parent = new int[n];
boolean[] visit = new boolean[n];
ArrayList<Node> al = new ArrayList<>();
for(int i = 0; i < n; i++) al.add(new Node(i));
for(int i = 1; i < n; i++) {
line = getLine();
int v1 = toi(line[0]) - 1, v2 = toi(line[1]) - 1;
al.get(v1).list.add(v2);
al.get(v2).list.add(v1);
}
Queue<Integer> q = new LinkedList<>();
q.add(0);
while(!q.isEmpty()) {
int cur = q.poll();
if(visit[cur]) continue;
visit[cur] = true;
for(int nodeIdx : al.get(cur).list) {
if(visit[nodeIdx]) continue;
parent[nodeIdx] = cur;
q.add(nodeIdx);
}
}
for(int i = 1; i < n; i++) sb.append(parent[i] + 1).append("\n");
print(sb);
}
static class Node {
int idx;
ArrayList<Integer> list = new ArrayList<>();
Node(int idx) { this.idx = idx; }
}
static int sum(int[] arr, int s, int e) { int sum = 0; for(int i = s; i <= e; i++) sum+=arr[i]; return sum; }
static int toi(String s) { return Integer.parseInt(s); }
static String[] getLine() throws IOException { return br.readLine().split(" "); }
static <T> void print(T s) { System.out.print(s); }
static <T> void println(T s) { System.out.println(s); }
}