백준 11725번 C++ 풀이

#include <iostream>
#include <queue>
#include <vector>
#define MAX 100001

using namespace std;
vector<int>  adj[MAX];
bool isVisited[MAX] = {false};
int parent[MAX];
int n;
int main() {
    cin.tie(NULL);
    ios::sync_with_stdio(false);

    cin >> n;
    for (auto i=1; i<n; i++){
        int a, b;
        cin >> a >> b;
        adj[a].push_back(b);
        adj[b].push_back(a);
    }
    queue<int> q;
    q.push(1);
    while (!q.empty()){
        int front = q.front();
        q.pop();
        isVisited[front] = true;
        int size = adj[front].size();
        for (int i =0; i<size; i++){
            int node = adj[front][i];
            if (!isVisited[node]){
                parent[node] = front;
                isVisited[node] = true;
                q.push(node);
            }
        }
    }
    for (int i =2; i<=n; i++){
        cout << parent[i] << '\n';
    }
    return 0;
}