题解

#include <bits/stdc++.h>
using namespace std;
int n, m;
vector<int> v[105];
int f[110], vis[110];
void bfs(int st) {
	queue<int> q;
	q.push(st);
	vis[st] = 1;
	while (!q.empty()) {
		int cp = q.front();
		q.pop();
		for (int i = 0; i < v[cp].size(); i++) {
			int np = v[cp][i];
			if (!vis[np]) {
				vis[np] = 1;
				q.push(np);
				f[np] = cp;
			}
		}
	}
}
int main() {
	cin >> n ;
	for (int i = 1; i < n; i++) {
		int x, y;
		cin >> x >> y;
		v[x].push_back(y);
		v[y].push_back(x);
	}
	bfs(1);
	for (int i = 2; i <= n; i++)
		cout << f[i] << " ";
	return 0;
}