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#include "sabotaz.h"
#include "message.h"

#include <algorithm>
#include <iostream>
#include <vector>

using namespace std;

class FindUnion {
 public:
  FindUnion(const int n) : parent_(n, -1) {}

  int Find(int a) {
    int b = a;
    while (parent_[b] >= 0) b = parent_[b];
    while (a != b) {
      const int c = parent_[a];
      parent_[a] = b;
      a = c;
    }
    return b;
  }

  void Merge(const FindUnion& f) {
    for (int i = 0; i < parent_.size(); ++i) if (f.parent_[i] >= 0) Union(i, f.parent_[i]);
  }

  void ReceiveFrom(const int source) {
    // cerr << "Trying to get something from " << source << endl;
    for (int i = 0; i < parent_.size(); ++i) {
      if ((i & 0x7ff) == 0) {
        // cerr << "Attempting pull from " << source << endl;
        Receive(source);
        // cerr << "Pull from " << source << " successful." << endl;
      }
      parent_[i] = GetInt(source);
    }
  }

  void SendTo(const int target) const {
    for (int i = 0; i < parent_.size(); ++i) {
      PutInt(target, parent_[i]);
      if ((i & 0x7ff) == 0x7ff || i + 1 == parent_.size()) {
        // cerr << "Push to " << target << " at " << i << endl;
        Send(target);
      }
    }
  }

  void Union(int a, int b) {
    a = Find(a);
    b = Find(b);
    if (a == b) return;
    if (parent_[a] < parent_[b]) {
      parent_[a] += parent_[b];
      parent_[b] = a;
    } else {
      parent_[b] += parent_[a];
      parent_[a] = b;
    }
  }

 private:
  vector<int> parent_;
};

vector<int> Split(const long long len, const long long parts) {
  vector<int> ret(parts + 1);
  for (int i = 0; i <= parts; ++i) ret[i] = (len * i) / parts;
  return ret;
}

int preorder_index = 0;
vector<int> preorder;
vector<int> span_boundary;
vector<pair<int, int>> span;

void AddNumber(const int a) {
  if (preorder[a] >= 0) return;
  preorder[a] = preorder_index++;
  for (int i = span_boundary[a]; i < span_boundary[a + 1]; ++i) AddNumber(span[i].second);
}

int res = 0;
vector<int> H;
vector<int> L;
vector<int> ND;

bool CheckBridge(const int a) {
  if (ND[a]) return false;
  ND[a] = 1;
  for (int i = span_boundary[a]; i < span_boundary[a + 1]; ++i) {
    const int b = span[i].second;
    if (CheckBridge(b)) {
      // cerr << "Returned from " << b << ": " << L[b] << ' ' << preorder[b] << ' ' << H[b] << ' ' << ND[b] << endl;
      if (L[b] == preorder[b] && H[b] < preorder[b] + ND[b]) ++res;
      L[a] = min(L[a], L[b]);
      H[a] = max(H[a], H[b]);
      ND[a] += ND[b];
    }
  }
  return true;
}

int main() {
  long long N = NumberOfIsles();
  long long M = NumberOfBridges();

  const int node = MyNodeId();
  const int nodes = NumberOfNodes();
  vector<int> bridge_bounds = Split(M, nodes);

  FindUnion f_left(N), f_me(N), f_other(N), f_parent(N), f_right(N);

  vector<pair<int, int>> bridges(bridge_bounds[node + 1] - bridge_bounds[node]);
  for (int i = bridge_bounds[node], j = 0; i < bridge_bounds[node + 1]; ++i, ++j) {
    bridges[j] = make_pair(BridgeEndA(i), BridgeEndB(i));
    f_me.Union(bridges[j].first, bridges[j].second);
  }

  const int left = (2 * node) + 1;
  const int parent = (node - 1) / 2;
  const int right = (2 * node) + 2;

  const bool has_left = left < nodes;
  const bool has_parent = node > 0;
  const bool has_right = right < nodes;

  if (has_left) {
    f_left.ReceiveFrom(left);
    f_other.Merge(f_left);
  }
  if (has_right) {
    f_right.ReceiveFrom(right);
    f_other.Merge(f_right);
  }
  if (has_parent) {
    f_parent.Merge(f_me);
    if (has_left || has_right) f_parent.Merge(f_other);
    f_parent.SendTo(parent);
    f_parent.ReceiveFrom(parent);
    f_other.Merge(f_parent);
  }
  if (has_left) {
    f_right.Merge(f_me);
    if (has_parent) f_right.Merge(f_parent);
    f_right.SendTo(left);
  }
  if (has_right) {
    f_left.Merge(f_me);
    if (has_parent) f_left.Merge(f_parent);
    f_left.SendTo(right);
  }

  // cerr << "Transfer done " << node << endl;

  vector<bool> in_span(bridges.size(), false);
  f_me = f_other;
  for (int i = 0; i < bridges.size(); ++i) {
    const int a = f_other.Find(bridges[i].first);
    const int b = f_other.Find(bridges[i].second);
    bridges[i] = make_pair(a, b);
    if (f_me.Find(a) != f_me.Find(b)) {
      // cerr << node << " bridge " << a << ' ' << b << endl;
      in_span[i] = true;
      f_me.Union(a, b);
      span.push_back(make_pair(a, b));
      span.push_back(make_pair(b, a));
    }
  }
  sort(span.begin(), span.end());
  {
    int i = 0;
    while (i < span.size()) {
      while (span[i].first >= span_boundary.size()) span_boundary.push_back(i);
      ++i;
    }
    while (N >= span_boundary.size()) span_boundary.push_back(i);
  }

  preorder.resize(N, -1);
  for (int i = 0; i < N; ++i) AddNumber(i);

  H = preorder;
  L = preorder;
  ND.resize(N, 0);
  for (int i = 0; i < bridges.size(); ++i) if (!in_span[i]) {
    const int a = bridges[i].first;
    const int b = bridges[i].second;
    H[a] = max(H[a], preorder[b]);
    H[b] = max(H[b], preorder[a]);
    L[a] = min(L[a], preorder[b]);
    L[b] = min(L[b], preorder[a]);
  }
  for (int i = 0; i < N; ++i) CheckBridge(i);

  // cerr << node << ' ' << res << endl;
  PutInt(0, res);
  Send(0);

  if (node == 0) {
    res = 0;
    for (int i = 0; i < nodes; ++i) {
      Receive(i);
      res += GetInt(i);
    }
    cout << res << endl;
  }

  return 0;
}