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#include "sabotaz.h"
#include "message.h"
#include<bits/stdc++.h>
#define ST first
#define ND second
using namespace std;
using LL = long long;
using PII = pair<int, int>;
const int N = 2e5;

int n, m;

int repr[N];
int rankk[N];

int find(int u){
  return repr[u] == u ? u : repr[u] = find(repr[u]);
}

void merge(int u, int v){
  u = find(u); v = find(v);
  if(rankk[u] == rankk[v]) rankk[v]++;
  if(rankk[u] > rankk[v]) swap(u, v);
  repr[u] = v;
}

struct edge {
  int v;
  int i;
  edge(int v, int i):v(v),i(i){}
};

vector<edge> g[N];
int gsize;
void addedge(int u, int v){
  g[u].emplace_back(v, gsize);
  g[v].emplace_back(u, gsize);
  gsize++;
}

int depth[N];
int dfs(int u, int d, int i){
//  cout << "dfs(" << u << ", " << d << ", " << i << ")" << endl;
  depth[u] = d;
  int lowdepth = d + 1;
  for(edge e : g[u]) if(e.i != i){
    if(depth[e.v] != -1){
      merge(u, e.v);
      //cout << "merge" << u << e.v << " (-)" << endl;
      //cout << "lowdepth " << lowdepth << " depth " << depth[e.v];
      lowdepth = min(lowdepth, depth[e.v]);
    } else {
      int s = dfs(e.v, d+1, e.i);
      if(s <= depth[u]){
    //    cout << "merge" << u << e.v << " (+)" << endl;
        merge(u, e.v);
        lowdepth = min(lowdepth, s);
      }
      lowdepth = min(lowdepth, s);
    }
  }
  //cout << "low(" << u << ") = " << lowdepth << endl;
  return lowdepth;
}

vector<PII> edges;

vector<vector<int>> classes;
int bridges;
void minimizegraph(){
  gsize = 0;
  fill_n(g, n, vector<edge>());
  for(PII p : edges){
    addedge(p.ST, p.ND);
  }
  
  fill_n(depth, n, -1);
  fill_n(rankk, n, 0);
  iota(repr, repr + n, 0);
  
  for(int u = 0; u < n; u++) if(depth[u] == -1){
    dfs(u, 0, -1);
  }

  vector<PII> newedges;
  bridges = 0;
  for(int u = 0; u < n; u++){
    for(edge e : g[u]){
      if(e.v < u && find(e.v) != find(u)){
        bridges++;
        newedges.push_back(PII(e.v, u));
      }
    }
  }
  classes.resize(n);
  fill_n(classes.begin(), n, vector<int>());
  for(int u = 0; u < n; u++){
    classes[find(u)].push_back(u);
  }
  for(int i = 0; i < n; i++){
    if(classes[i].size() > 1){
      for(int j = 0; j < (int) classes[i].size(); j++){
        //cout << classes[i][j] << " ";
        newedges.emplace_back(classes[i][j], classes[i][(j+1)%classes[i].size()]);
      }
      //cout << endl;
    }
  }
  edges = newedges;
}
void printgraph(){
  //for(PII e : edges) printf("%d %d\n", e.ST, e.ND);
  //printf("=========\n");
  //printf("%d\n", bridges);
}

const int EDGES_IN_MESSAGE = 1000;
int main(){
  int numberOfNodes = NumberOfNodes();
  int myNodeId = MyNodeId();
  n = NumberOfIsles();
  m = NumberOfBridges();
  int begin = (LL) myNodeId * m / numberOfNodes;
  int end = (LL) (myNodeId + 1) * m / numberOfNodes;
  for(int i = begin; i < end; i++){
    int a = BridgeEndA(i);
    int b = BridgeEndB(i);
    edges.emplace_back(a, b);
  }
  printgraph();
  minimizegraph();
  printgraph();
  for(int i = 0; (1<<i) <= numberOfNodes - 1; i++){
    int yourNodeId = myNodeId ^ (1<<i);
    if(yourNodeId >= numberOfNodes) continue;
    if(myNodeId & (1<<i)){
      PutInt(yourNodeId, edges.size());
      Send(yourNodeId);
      for(int j = 0; j < (edges.size() + EDGES_IN_MESSAGE - 1) / EDGES_IN_MESSAGE; j++){
        for(int k = j * EDGES_IN_MESSAGE; k < min((j+1) * EDGES_IN_MESSAGE, (int)edges.size()); k++){
          //cout << "k = " << k << " e = " << edges[k].ST << " " << edges[k].ND << endl;
          PutInt(yourNodeId, edges[k].ST);
          PutInt(yourNodeId, edges[k].ND);
        }
        Send(yourNodeId);
      }
      return 0;
    } else {
      Receive(yourNodeId);
      int size = GetInt(yourNodeId);
      for(int j = 0; j < (size + EDGES_IN_MESSAGE - 1) / EDGES_IN_MESSAGE; j++){
        Receive(yourNodeId);
        for(int k = j * EDGES_IN_MESSAGE; k < min((j+1) * EDGES_IN_MESSAGE, size); k++){
          int a = GetInt(yourNodeId);
          int b = GetInt(yourNodeId);
          edges.emplace_back(a, b);
        }
      }
      printgraph();
      minimizegraph();
      printgraph();
    }
  }
  printf("%d\n", bridges);
}