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#include "sabotaz.h"
#include <message.h>

#include <cstring>
#include <cstdio>
#include <algorithm>
#include <vector>

using namespace std;

void recv_data( int src, void *buf, size_t size ) {
    int *s = (int*)buf;
    for ( int i=0; i<size/4; i++ ) {
         s[i] = GetInt( src );
    }
}

#define recv_struct( src, s ) recv_data( src, (void*)&s, sizeof(s) )

void send_data( int dst, void *buf, size_t size ) {
    int *s = (int*)buf;
    for ( int i=0; i<size/4; i++ ) {
         PutInt( dst, s[i] );
    }
    Send(dst);
}

#define send_struct( dst, s ) send_data( dst, (void*)&s, sizeof(s) )

int FU[ 200005 ];
int ODW[ 200005 ];
int K[ 10000007 ];
int Z[ 3333333 ];
int fu( int a ) { if (FU[a]!=-1) return FU[a]=fu(FU[a]); return a; }

vector<pair<int,int> > KR[200005];

int DFS( int v, int pp, int d ) {
    if ( ODW[v] ) return ODW[v];
    ODW[v]=d;
    int c = d;
    for ( auto &i : KR[v] ) if ( i.second != pp ) {
        int a = DFS( i.first, i.second, d+1 );
        if ( a <= d ) {
            Z[ i.second ] = 0;
            c = min( c, a );
        }
    }
    return c;
}

#define send_max_msg (16*1024)

int main() {
    int n = NumberOfIsles();
    int m = NumberOfBridges();
    //printf("%d %d\n",n,m);
    int inst_count = NumberOfNodes();
    int inst = MyNodeId();

    //if ( !inst ) fprintf( stderr, "n=%d m=%d\n", n, m );


    for ( int i=0; i<n; i++ ) { ODW[i]=0; FU[i]=-1; }

    int b = ((long long)m)*(inst)/inst_count;
    int e = ((long long)m)*(inst+1)/inst_count;

    int ilz = 0;

    for ( int i=b; i<e; i++ ) {
        int a=BridgeEndA( i ); int b=BridgeEndB( i );
        KR[a].push_back( make_pair( b, ilz ) );
        KR[b].push_back( make_pair( a, ilz ) );
        Z[ ilz++ ] = 1;
    }

    int ilk = 0;


    int s1 = (inst+1)*2   -1;
    if ( s1<inst_count ) {
        Receive( s1 );
        recv_struct( s1, ilk );
        for ( int it = 0; it < ilk; it += send_max_msg ) {
            Receive( s1 );
            recv_data( s1, K+it, min( ilk-it, send_max_msg )*sizeof( *K ) );
        } 
    }

    int s2 = (inst+1)*2+1  -1;
    if ( s2<inst_count ) {
        Receive( s2 );
        int nr;
        recv_struct( s2, nr );
        int it = ilk; ilk += nr;
        for ( ; it < ilk; it += send_max_msg ) {
            Receive( s2 );
            recv_data( s2, K+it, min( ilk-it, send_max_msg )*sizeof( *K ) );
        }
    }

    for ( int i=0; i<ilk; i+=3 ) {
        int a = K[i]; int b = K[i+1]; int c = K[i+2];
        KR[a].push_back( make_pair( b, ilz ) );
        if ( a!=b  ) KR[b].push_back( make_pair( a, ilz ) );
        Z[ilz++] = c;
    }

    for ( int i=0; i<n; i++ ) {
        if ( !ODW[i] ) DFS( i, -1, 1 );
    }
 
    ilk = 0;
    for ( int i=0; i<n; i++ )
        for ( auto &j : KR[i] ) if ( j.first < i  ) {
            int a = i; int b = j.first; int c = Z[j.second];
            if ( fu(a) != fu(b) ) {
                FU[fu(a)] = fu(b);
                K[ilk++] = a; K[ilk++] = b;
                K[ilk++] = c;
            }
        }

    if ( inst ) {
       int dst_inst = (inst+1)/2  -1;
       send_struct( dst_inst, ilk );
       for ( int it = 0; it < ilk; it += send_max_msg ) {
            send_data( dst_inst, K+it, min( ilk-it, send_max_msg )*sizeof( *K ) );
       }
    } else {
        int w = 0;
        //for ( int i=0; i<ilz; i++ ) w += Z[i];
        for ( int i=2; i<ilk; i+=3 ) w += K[i];
        printf("%d\n",w);
    }
    return 0;
}