Submission #1133395

#	Time	Username	Problem	Language	Result	Execution time	Memory
1133395		Kubeti	Pipes (CEOI15_pipes)	C++20	100 / 100	1771 ms	14984 KiB

pipes

#include <bits/stdc++.h>

using namespace std;

const int nmax = 1e5 + 1, mod = 1e6 + 7;

struct DSU {
  int root[nmax];

  void init(int n) {
    for(int i = 1; i <= n; i++) {
      root[i] = i;
    }
  }

  int find(int a) {
    if(root[a] == a) {
      return a;
    }
    return root[a] = find(root[a]);
  }

  void unite(int a, int b) {
    assert(a != b);
    root[a] = b;
  }
} d1, d2;

vector<int> adj[nmax];
int low[nmax];
int t[nmax];
bitset<nmax> f;
int timer = 0;

void dfs(int i, int tata) {
  f[i] = 1;
  t[i] = low[i] = timer++;
  bool ok = 0;
  for(auto it : adj[i]) {
    if(it == tata && !ok) {
      ok = 1;
      continue;
    }
    if(f[it]) {
      low[i] = min(low[i], t[it]);
    } else {
      dfs(it, i);
      low[i] = min(low[i], low[it]);
      if(t[i] < low[it]) {
        cout << i << " " << it << '\n';
      }
    }
  }
}

int32_t main(){
  int n, m;
  cin >> n >> m;
  d1.init(n), d2.init(n);
  int cnt = 0;
  int a, b;
  while(m--) {
    cin >> a >> b;
    if(d1.find(a) != d1.find(b)) {
      d1.unite(d1.find(a), d1.find(b));
      adj[a].push_back(b);
      adj[b].push_back(a);
    } else if(d2.find(a) != d2.find(b)) {
      d2.unite(d2.find(a), d2.find(b));
      adj[a].push_back(b);
      adj[b].push_back(a);
    }
  }
  for(int i = 1; i <= n; i++) {
    if(!f[i]) {
      dfs(i, 0);
    }
  }
  return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10