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

using namespace std;

typedef long long LL;

template<typename TH>
void debug_vars(const char* data, TH head){
    cerr << data << "=" << head << "\n";
}

template<typename TH, typename... TA>
void debug_vars(const char* data, TH head, TA... tail){
    while(*data != ',') cerr << *data++;
    cerr << "=" << head << ",";
    debug_vars(data+1, tail...);
}

#ifdef LOCAL
#define debug(...) debug_vars(#__VA_ARGS__, __VA_ARGS__)
#else
#define debug(...) (__VA_ARGS__)
#endif

/////////////////////////////////////////////////////////


const int SendAfter = 63990;

struct Sender {
    enum FieldType { FLD_CHAR, FLD_INT, FLD_LL };
    struct field {
        FieldType type;
        union { char ch; int n; LL l; };
    };
    struct Submitter {};

    vector<field> toSend;
    int dest;
    int cap;

    Sender() : dest(-10000), cap(SendAfter) {}
    Sender(int dst){
        dest = dst;
        cap = SendAfter;
        toSend.clear();
    }
    ~Sender(){
        if(toSend.size() > 0) submit();
    }

    int capacity() const { return cap; }
    void capacity(int newCapacity) { cap = newCapacity; }
    
    void submit(){
        LL msgsize = 4;
        if(toSend.size() == 0) return;
        debug(toSend.size());
        PutInt(dest, (int)toSend.size());
        for(auto& f : toSend){
            switch(f.type){
                case FLD_CHAR: PutChar(dest, f.ch); msgsize++; break;
                case FLD_INT:  PutInt(dest, f.n); msgsize += 4; break;
                case FLD_LL:   PutLL(dest, f.l); msgsize += 8; break;
                default:       assert(false);
            }
        }
        debug("submit", dest, msgsize);
        Send(dest);
        toSend.clear();
    }

    void add_field(field f){
        assert(dest >= 0);
        toSend.push_back(f);
        if(toSend.size() >= cap) submit();
    }

    friend Sender& operator<<(Sender& snd, char ch){
        field f; f.type = FLD_CHAR; f.ch = ch; snd.add_field(f); return snd;
    }
    friend Sender& operator<<(Sender& snd, int n){
        field f; f.type = FLD_INT; f.n = n; snd.add_field(f); return snd;
    }
    friend Sender& operator<<(Sender& snd, LL l){
        field f; f.type = FLD_LL; f.l = l; snd.add_field(f); return snd;
    }
    friend Sender& operator<<(Sender& snd, Sender::Submitter){
        snd.submit(); return snd;
    }
};
Sender::Submitter submit;


struct Receiver {
    int numEnqueued;
    int node;

    Receiver() : node(-10000) {}
    Receiver(int nod) : node(nod), numEnqueued(0) {}

    void try_fetch(){
        assert(node >= -1);
        assert(numEnqueued >= 0);
        if(numEnqueued > 0){ numEnqueued--; return; }
        //debug("fetch", node);
        Receive(node);
        numEnqueued = GetInt(node);
        numEnqueued--;
        //debug(numEnqueued);
    }

    char read_char(){ try_fetch(); return GetChar(node); }
    int read_int(){ try_fetch(); return GetInt(node); }
    LL read_ll(){ try_fetch(); return GetLL(node); }

    friend Receiver& operator>>(Receiver& recv, char& ch){
        ch = recv.read_char(); return recv;
    }
    friend Receiver& operator>>(Receiver& recv, int& n){
        //debug("!!!", recv.node, recv.numEnqueued);
        n = recv.read_int(); return recv;
    }
    friend Receiver& operator>>(Receiver& recv, LL& l){
        l = recv.read_ll(); return recv;
    }
};

template<typename T>
Sender& operator<<(Sender& snd, const vector<T>& vec){
    snd << (int)vec.size();
    //debug(vec.size());
    for(T v : vec) snd << v;
    return snd;
}

template<typename T>
Receiver& operator>>(Receiver& recv, vector<T>& vec){
    int sz;
    recv >> sz;
    vec = vector<T>(sz);
    //debug(sz);
    for(int i = 0; i < sz; i++){
        //debug(sz, i);
        recv >> vec[i];
        //debug(sz, i);
    }
    return recv;
}


const int MaxN = 200005,
          MaxM = 10000005;

LL MyNode;
LL TotalNodes, NumNodes;
LL N, M;
vector<Sender> senders;
vector<Receiver> receivers;

void init(){
    MyNode     = MyNodeId();
    TotalNodes = NumberOfNodes();
    for(LL i = 0; i < TotalNodes; i++){
        senders.emplace_back(i);
        receivers.emplace_back(i);
    }
    N = NumberOfIsles();
    M = NumberOfBridges();
}

vector<vector<pair<int,int>>> adj;
bool visited[MaxN];
int ctm = -31337;
int lowVert[MaxN], inTime[MaxN], bestEdge[MaxN];
vector<int> edgesIds;

void dfs(int v, int efrom){
    lowVert[v] = inTime[v] = (++ctm);
    bestEdge[v] = -1;
    visited[v] = true;

    for(auto& P : adj[v]){
        int s, e;
        tie(s,e) = P;
        //debug(v,s,e);
        if(e == efrom) continue;
        if(visited[s]){
            if(inTime[s] < lowVert[v]){
                lowVert[v]  = inTime[s];
                bestEdge[v] = e;
            }
        } else {
            edgesIds.push_back(e);
            dfs(s, e);
            if(lowVert[s] < lowVert[v]){
                lowVert[v]  = lowVert[s];
                bestEdge[v] = -1;
            }
        }
    }
}

// redukcja zbioru krawedzi do takiego, ktory jednoznacznie wyznacza uklad
// dwuspojnych / spojnosci
// wejscie: (edgesIds) - numery krawedzi w wejsciowym grafie
// wyjscie: liczba mostow; (edgesIds) - nr. krawedzi
LL reduce(){
    // budujemy graf
    adj.clear();
    adj.resize(N);
    for(int e : edgesIds){
        int u = BridgeEndA(e),
            v = BridgeEndB(e);
        if(u != v){
            adj[u].emplace_back(v, e);
            adj[v].emplace_back(u, e);
        }
    }

    // odpalamy Tarjana
    fill(visited, visited+N+1, false);
    edgesIds.clear();
    ctm = 0;
    LL numBridges = 0;
    for(int v = 0; v < N; v++){
        if(!visited[v]){
            dfs(v, -1);
            numBridges--; // spojna potem policzymy jako most
        }
    }

    // liczymy mosty
    for(int v = 0; v < N; v++){
        //debug(v, lowVert[v], inTime[v]);
        if(lowVert[v] >= inTime[v]) numBridges++;
    }

    // zapisujemy wyniki: krawedzie drzewowe i fajne powrotne
    for(int v = 0; v < N; v++){
        if(bestEdge[v] != -1) edgesIds.push_back(bestEdge[v]);
    }

    return numBridges;
}


int main(){
    init();
    if(MyNode >= M) return 0;
    NumNodes = min(TotalNodes, M);
    
    LL left = (M * MyNode) / NumNodes, right = (M * (MyNode+1)) / NumNodes;
    edgesIds = vector<int>(right-left);
    iota(edgesIds.begin(), edgesIds.end(), (int)left);

    LL Base = 1;
    while(Base < NumNodes) Base *= 2;
    LL mostright = Base + NumNodes - 1;
    vector<int> curNode(Base*2);
    for(LL i = Base; i <= mostright; i++) curNode[i] = i-Base;
    for(LL i = mostright+1; i < 2*Base; i++) curNode[i] = -1;
    for(LL i = Base-1; i >= 1; i--) curNode[i] = curNode[i*2];

    LL effectiveId = MyNode + Base;
    if(MyNode == 0){
        for(int i = 0; i <= (int)mostright; i++){
            debug(i, curNode[i]);
        }
    }
    LL numBridges;

    while(effectiveId > 0 && curNode[effectiveId] == MyNode){
        if(effectiveId < Base){
            vector<int> rightChild;
            // odbieramy dane z curNode[eid*2+1]
            int pullee = curNode[effectiveId*2+1];
            if(pullee != -1){
                debug(pullee);
                receivers[pullee] >> rightChild;
                for(int v : rightChild) edgesIds.push_back(v);
            }
        }

        numBridges = reduce();

        effectiveId /= 2;
        mostright /= 2;
    }

    // nie root? wysylamy uprawnionej jednostce
    if(MyNode != 0){
        int target = curNode[effectiveId];
        debug("pushing to ", target);
        senders[target] << edgesIds << submit;
    } else {
        // oh, root!
        cout << numBridges << endl;
    }
    return 0;
}