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#include "message.h"
#include "sabotaz.h"
#include <bits/stdc++.h>
#include <assert.h>

#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define FORD(i, a, b) for(int i = (a); i >= (b); --i)
#define VAR(v, i) __typeof(i) v=(i)
#define FORE(i, c) for(VAR(i, (c).begin()); i != (c).end(); ++i)
#define all(v) (v).begin(),(v).end()

#define VI vector<int>
#define PII pair<int,int>
#define st first
#define nd second
#define mp make_pair
#define pb push_back
#define lint long long int

#define debug(x) {cerr <<#x <<" = " <<x <<endl; }
#define debug2(x,y) {cerr <<#x <<" = " <<x << ", "<<#y<<" = "<< y <<endl; } 
#define debug3(x,y,z) {cerr <<#x <<" = " <<x << ", "<<#y<<" = "<< y << ", " << #z << " = " << z <<endl; } 
#define debugv(x) {{cerr <<#x <<" = "; FORE(itt, (x)) cerr <<*itt <<", "; cerr <<endl; }}
#define debugt(t,n) {{cerr <<#t <<" = "; FOR(it,0,(n)) cerr <<t[it] <<", "; cerr <<endl; }}

using namespace std;

int n,m;
set<int> g[200005];
int in[200005];
int pi[200005];
set<PII> podwojne;
vector<PII> mosty;
int cnt = 1;


int dfs(int u) {
  int ans = u;
  in[u] = cnt++;
  FORE(i,g[u]){
    int v = *i;
    if (v == pi[u]) continue;
    if (in[v] == 1e9) {
      pi[v] = u;
      v = dfs(v);
    }
    if (in[ans] > in[v]) ans = v;
  }
  if (ans == u && pi[u]!=u) {
    mosty.pb(mp(u,pi[u]));
  }
  return ans;
}


int main() {
  int myId = MyNodeId();
  n = NumberOfIsles();
  m = NumberOfBridges();
  if (myId == 0) {
    int ans = 0;
    FOR(i,0,m) {
      int u = BridgeEndA(i), v = BridgeEndB(i);
      if (u != v) {
        if(g[v].find(u) != g[v].end()) podwojne.insert(mp(v,u));
        else {
          g[v].insert(u);
          g[u].insert(v);
        }
      }
    }
    FOR(i,0,n) in[i] = 1e9;
    FOR(i,0,n) {
      if(in[i] == 1e9){
        pi[i] = i; dfs(i);
      }
    }  
    FOR(i,0,mosty.size()) {
      if(podwojne.find(mosty[i]) == podwojne.end()) {
        PII xx = mp(mosty[i].nd, mosty[i].st);
        if(podwojne.find(xx) == podwojne.end()) {
          ans++;
        }
      }
    }

    printf("%d\n",ans);
  }
}