Distances

#include <bits/stdc++.h>
#define pb push_back
#define f first
#define sc second
using namespace std;
typedef long long int ll;
typedef string str;
vector<vector<int>> v;
vector<int> order;
void dfs(int nd, int ss){
    for(int x: v[nd]) if(x!=ss) dfs(x, nd);
    order.pb(nd+1);
}
void solve(){
    int n; cin >> n;
    v.assign(n, {}), order.clear();
    for(int i = 1; i < n; i++){
        int a, b; cin >> a >> b; a--, b--;
        v[a].pb(b);
        v[b].pb(a);
    }
    dfs(0, -1);
    for(int x: order) cout << x << " ";
    cout << "\n";
}
int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int T; cin >> T; while(T--) solve();
}

Test 1

Group: 1, 2

Verdict: WRONG ANSWER

Test 2

Group: 2

Verdict: WRONG ANSWER