Distances

#include <bits/stdc++.h>
using namespace std;

#define pb push_back
#define fr first
#define sc second
#define clr(a, x) memset(a, x, sizeof(a))
#define dbg(x) cout<<"("<<#x<<"): "<<x<<endl;
#define printvector(arr) for (auto it = arr.begin(); it != arr.end(); ++it) cout<<*it<<" "; cout<<endl;
#define all(v) v.begin(), v.end()
#define lcm(a, b) (a * b)/__gcd(a, b)
#define int long long int
#define printvecpairs(vec) for(auto it: vec) cout<<it.fr<<' '<<it.sc<<endl;
#define endl '\n'
#define float long double

const int MOD = 1e9 + 7;
const int INF = 2e15;
const int MAXN = 1e5 + 5;

vector<int> adj[MAXN], poss[MAXN];
bool vis[MAXN];

void dfs(int s, int dist, int og){
	if(dist > 3){
		return;
	}
	vis[s] = true;
	poss[og].pb(s);
	for(auto it: adj[s]){
		if(!vis[it]){
			dfs(it, dist+1, og);
		}
	}
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    #ifdef LOCAL
    freopen("input.txt", "r", stdin);
    #endif
    int t;
    cin>>t;
    while(t--){
    	int n;
    	cin>>n;
    	for(int i= 0;i<=n+1;i++){
    		poss[i].clear();
    		adj[i].clear();
    	}
    	for(int i= 0;i<n-1;i++){
    		int t1, t2;
    		cin>>t1>>t2;
    		adj[t1].pb(t2);
    		adj[t2].pb(t1);
    	}
    	int a[n+2];
    	for(int i= 1;i<=n;i++){
    		clr(vis, 0);
    		a[i] = i;
    		dfs(i, 0, i);
    	}
    	do {
    		bool ans = true;
    		for(int i= 2;i<=n;i++){
    			bool flag = false;
    			for(int j: poss[a[i-1]]){
    				if(j == a[i]) {
    					flag = true;
    					break;
    				}
    			}
    			if(!flag){
    				ans = false;
    				break;
    			}
    		}
    		if(ans){
    			for(int i=1;i<=n;i++){
	    			cout<<a[i]<<' ';
	    		}
	    		cout<<endl;
	    		break;
    		}
    	} while(next_permutation(a+1, a+n+1));
    }

    return 0;
}

Test 1

Group: 1, 2

Verdict: ACCEPTED

Test 2

Group: 2

Verdict: TIME LIMIT EXCEEDED