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Submission #617601

# Submission time Handle Problem Language Result Execution time Memory
617601 2022-08-01T12:22:58 Z ollel Pipes (CEOI15_pipes) C++17
0 / 100
 4344 ms 65540 KB 
#include <bits/stdc++.h>
using namespace std;

typedef vector<int> vi;
typedef vector<vi> vvi;
typedef long long ll;
typedef pair<int,int> pii;

#define pb push_back
#define rep(i,a,b) for(int i = a; i < b; i++)

int n, m;

vi depth, back_edge;
vvi adj;
vi parent;
vvi children;

vector<pii> ans;

void dfs(int x, int cf) {
  parent[x] = cf;

  for (auto y : adj[x]) {
    if (y == parent[x]) continue;
    if (depth[y] != -1) {
      back_edge[x] = min(back_edge[x], depth[y]);
      continue;
    }
    children[x].pb(y);
    back_edge[y] = depth[y] = depth[x] + 1;
    dfs(y, x);
  }
}

void dfs2(int x) {
  for (auto & y : children[x]) dfs2(y);

  for (auto & y : children[x]) back_edge[x] = min(back_edge[x], back_edge[y]);
  if (depth[x] != 0) if (back_edge[x] >= depth[x]) ans.pb({x+1, parent[x]+1});
}

int main() {
  cin >> n >> m;

  adj.resize(n); depth.assign(n,-1); back_edge.assign(n,n);
  children.resize(n); parent.assign(n,-1);

  rep(i,0,m) {
    int a, b;
    cin >> a >> b;a--;b--;
    adj[a].pb(b);
    adj[b].pb(a);
  }

  rep(i,0,n) {
    if (depth[i] != -1) continue;
    depth[i] = back_edge[i] = 0;
    dfs(i, -1);
    dfs2(i);
  }

  cout << ans.size() << endl;
  for (auto [x, y] : ans) {
    cout << x << " " << y << endl;
  }
}

Subtask #1
0 / 10.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 212 KB Unexpected end of file - int32 expected
2 Halted 0 ms 0 KB -

Subtask #2
0 / 10.0

# Verdict Execution time Memory Grader output
1 Incorrect 9 ms 1108 KB Unexpected end of file - int32 expected
2 Halted 0 ms 0 KB -

Subtask #3
0 / 10.0

# Verdict Execution time Memory Grader output
1 Incorrect 343 ms 14108 KB Unexpected end of file - int32 expected
2 Halted 0 ms 0 KB -

Subtask #4
0 / 10.0

# Verdict Execution time Memory Grader output
1 Runtime error 627 ms 21864 KB Memory limit exceeded
2 Halted 0 ms 0 KB -

Subtask #5
0 / 10.0

# Verdict Execution time Memory Grader output
1 Runtime error 1202 ms 40016 KB Memory limit exceeded
2 Halted 0 ms 0 KB -

Subtask #6
0 / 10.0

# Verdict Execution time Memory Grader output
1 Runtime error 1842 ms 52152 KB Memory limit exceeded
2 Halted 0 ms 0 KB -

Subtask #7
0 / 10.0

# Verdict Execution time Memory Grader output
1 Runtime error 3156 ms 65540 KB Memory limit exceeded
2 Halted 0 ms 0 KB -

Subtask #8
0 / 10.0

# Verdict Execution time Memory Grader output
1 Runtime error 3680 ms 65536 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -

Subtask #9
0 / 10.0

# Verdict Execution time Memory Grader output
1 Runtime error 4344 ms 65536 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -

Subtask #10
0 / 10.0

# Verdict Execution time Memory Grader output
1 Runtime error 4043 ms 65540 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -