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  1. 	#include <iostream>
  2. 	#include <vector>
  3. 	#include <set>
  4. 	#include <algorithm>
  5.  
  6. 	using namespace std;
  7.  
  8. 	const int MAXN = 100005;
  9. 	vector<int> adj[MAXN];
  10. 	bool visited[MAXN];
  11. 	int tin[MAXN], low[MAXN], timer;
  12. 	set<pair<int, int>> bridges;
  13.  
  14. 	bool dfsCheck(int u, int target) {
  15. 	    visited[u] = true;
  16. 	    if (u == target) return true;
  17. 	    for (int v : adj[u]) {
  18. 	        if (!visited[v] && dfsCheck(v, target)) return true;
  19. 	    }
  20. 	    return false;
  21. 	}
  22.  
  23. 	void tim_canh_cau(int n) {
  24. 	    for (int u = 1; u <= n; ++u) {
  25. 	        for (int v : adj[u]) {
  26. 	            if (u < v) {
  27.  
  28. 	                adj[u].erase(remove(adj[u].begin(), adj[u].end(), v), adj[u].end());
  29. 	                adj[v].erase(remove(adj[v].begin(), adj[v].end(), u), adj[v].end());
  30.  
  31. 	                fill(visited, visited + n + 1, false);
  32. 	                if (!dfsCheck(u, v)) {
  33. 	                    cout << u << " "<< v << endl;
  34. 	                }
  35.  
  36.  
  37. 	                adj[u].push_back(v);
  38. 	                adj[v].push_back(u);
  39. 	            }
  40. 	        }
  41. 	    }
  42. 	}
  43. 	int main() {
  44. 	    int n, m;
  45. 	    cin >> n >> m;
  46. 	    for (int i = 0; i < m; i++) {
  47. 	        int u, v;
  48. 	        cin >> u >> v;
  49. 	        adj[u].push_back(v);
  50. 	        adj[v].push_back(u);
  51. 		}
  52. 		tim_canh_cau(n);
  53. 	}
  54.  
Success #stdin #stdout 0.01s 5824KB
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https://ideone.com/QQQLWk
language:
C++ (gcc 8.3)
created:
5 days ago
visibility:
public

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