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  1. #include <bits/stdc++.h>
  2. using namespace std;
  3.  
  4. #define faster ios_base::sync_with_stdio(false); cin.tie(NULL)
  5. #define fi first
  6. #define se second
  7. #define ll long long
  8. #define ii pair<int,int>
  9. #define BIT(mask, i) ((mask >> i) & 1)
  10. #define c_BIT(mask) __builtin_popcount(mask)
  11.  
  12. const int N = 605;
  13.  
  14. int T, n, m, k;
  15. vector<int> adj[N];
  16. bool found;
  17. vector<int> ans;
  18.  
  19. bool is_adj(int u, int v) {
  20.     return binary_search(adj[u].begin(), adj[u].end(), v);
  21. }
  22.  
  23. void BronKerbosch(vector<int> R, vector<int> P, vector<int> X) {
  24.     if (found) return;
  25.     if ((int)R.size() == k) {
  26.         ans = R;
  27.         found = true;
  28.         return;
  29.     }
  30.     if ((int)R.size() + (int)P.size() < k) return;
  31.     if (P.empty() && X.empty()) return;
  32.  
  33.     int u = -1;
  34.     if (!P.empty()) u = P[0];
  35.     else if (!X.empty()) u = X[0];
  36.  
  37.     vector<int> candidates;
  38.     if (u == -1) candidates = P;
  39.     else {
  40.         unordered_set<int> neigh(adj[u].begin(), adj[u].end());
  41.         for (int v : P) if (!neigh.count(v)) candidates.push_back(v);
  42.     }
  43.  
  44.     for (int v : candidates) {
  45.         if (found) return;
  46.         vector<int> newR = R;
  47.         newR.push_back(v);
  48.  
  49.         vector<int> newP, newX;
  50.         for (int u : P)
  51.             if (is_adj(u, v)) newP.push_back(u);
  52.         for (int u : X)
  53.             if (is_adj(u, v)) newX.push_back(u);
  54.  
  55.         BronKerbosch(newR, newP, newX);
  56.  
  57.         P.erase(find(P.begin(), P.end(), v));
  58.         X.push_back(v);
  59.     }
  60. }
  61.  
  62. void solve() {
  63.     while (T--) {
  64.         cin >> n >> m >> k;
  65.         for (int i = 1; i <= n; i++) adj[i].clear();
  66.  
  67.         for (int i = 0; i < m; i++) {
  68.             int u, v; cin >> u >> v;
  69.             adj[u].push_back(v);
  70.             adj[v].push_back(u);
  71.         }
  72.         for (int i = 1; i <= n; i++) sort(adj[i].begin(), adj[i].end());
  73.  
  74.         found = false; ans.clear();
  75.         vector<int> R, P, X;
  76.         for (int i = 1; i <= n; i++) P.push_back(i);
  77.  
  78.         BronKerbosch(R, P, X);
  79.  
  80.         if (!found) cout << -1 << '\n';
  81.         else {
  82.             sort(ans.begin(), ans.end());
  83.             for (int i = 0; i < (int)ans.size(); i++)
  84.                 cout << ans[i] << (i + 1 == (int)ans.size() ? '\n' : ' ');
  85.         }
  86.     }
  87. }
  88.  
  89. void inp() {
  90.     cin >> T;
  91. }
  92.  
  93. int main() {
  94.     faster;
  95.     inp();
  96.     solve();
  97.     return 0;
  98. }
  99.  
Success #stdin #stdout 0s 5320KB
comments (?)
stdin 
Standard input is empty
stdout 
Standard output is empty
https://ideone.com/nqzTJX
language:
C++14 (gcc 8.3)
created:
10 days ago
visibility:
public

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