Submission #1085988

#	Time	Username	Problem	Language	Result	Execution time	Memory
1085988		juicy	Pipes (CEOI15_pipes)	C++17	50 / 100	777 ms	65536 KiB

pipes

#include <bits/stdc++.h>

using namespace std;

#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#endif

const int N = 1e5;

int n, m;
int low[N], num[N];
vector<int> g[N];

struct dsu {
  int pr[N];

  dsu() {
    memset(pr, -1, sizeof(pr));
  }

  int find(int u) {
    return pr[u] < 0 ? u : pr[u] = find(pr[u]);
  }

  bool mrg(int u, int v) {
    int a = find(u), b = find(v);
    if (a == b) {
      return 0;
    }
    pr[b] = a;
    g[u].push_back(v);
    g[v].push_back(u);
    return 1;
  }
} a, b;

int timer;

void dfs(int u, int p) {
  low[u] = num[u] = ++timer;
  bool flg = 0;
  for (int v : g[u]) {
    if (v == p && !flg) {
      flg = 1;
      continue;
    }
    if (!num[v]) {
      dfs(v, u);
      low[u] = min(low[u], low[v]);
      if (low[v] > num[u]) {
        cout << u + 1 << " " << v + 1 << "\n";
      }
    } else {
      low[u] = min(low[u], num[v]);
    }
  }
}

int main() {
  ios::sync_with_stdio(false); cin.tie(nullptr);

  cin >> n >> m;
  while (m--) {
    int u, v; cin >> u >> v; --u, --v;
    if (!a.mrg(u, v)) {
      b.mrg(u, v);
    }
  }
  for (int i = 0; i < n; ++i) {
    if (!num[i]) {
      dfs(i, i);
    }
  }
  return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10