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// Artur Kraska, II UWr

#include <algorithm>
#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <vector>
#include <cmath>
#include <list>
#include <set>
#include <map>

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

#define forr(i, n)                  for(int i=0; i<n; i++)
#define FOREACH(iter, coll)         for(typeof(coll.begin()) iter = coll.begin(); iter != coll.end(); ++iter)
#define FOREACHR(iter, coll)        for(typeof(coll.rbegin()) iter = coll.rbegin(); iter != coll.rend(); ++iter)
#define lbound(P,R,PRED)            ({typeof(P) X=P,RRR=(R), PPP = P; while(PPP<RRR) {X = (PPP+(RRR-PPP)/2); if(PRED) RRR = X; else PPP = X+1;} PPP;})
#define testy()                     int _tests; scanf("%d", &_tests); FOR(_test, 1, _tests)
#define CLEAR(tab)                  memset(tab, 0, sizeof(tab))
#define CONTAIN(el, coll)           (coll.find(el) != coll.end())
#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 MP                          make_pair
#define PB                          push_back
#define deb(X)                      X;

#define M 1000000007
#define INF 1000000007


using namespace std;

int n, m, numer;
long long res;

struct ww
{
    bool pa;
    int nr;
    int dss;
    int low;
    list <int> l;
};
ww tab[200005];

void wczytaj()
{
    int a, b;

    n = NumberOfIsles();
    m = NumberOfBridges();

    for(int i=0; i<m; i++)
    {
        a = BridgeEndA(i);
        b = BridgeEndB(i);
        tab[a].l.push_back(b);
        tab[b].l.push_back(a);
    }
}

void go(int v, int o)
{
    tab[v].nr = tab[v].low = numer;
    numer++;
    int ile = 0;

    for(list<int>::iterator it = tab[v].l.begin(); it != tab[v].l.end(); ++it)
    {
        if(*it == o)
        {
            ile++;
            continue;
        }
        if(tab[*it].nr == 0)
        {
            go(*it, v);
            tab[v].low = min(tab[v].low, tab[*it].low);
        }
        else   tab[v].low = min(tab[v].low, tab[*it].nr);
    }

    if(tab[v].low >= tab[o].nr)   tab[o].pa = 1;
    if(tab[v].low > tab[o].nr)
        if(ile <= 1)
            res++;//, printf("most %d-%d\n", o, v);
}

void punkty_artykulacji()
{
    int il = 0;
    numer = 2;
    tab[1].nr = tab[1].low = 1;

    for(list<int>::iterator it = tab[1].l.begin(); it != tab[1].l.end(); ++it)
        if(tab[*it].nr == 0)
        {
            go(*it, 1);
            il++;
            numer++;
        }
    tab[1].pa = il > 1;


//    for(int i=1; i<=n; i++)
//        printf("[%d] -> PA:%d\n", i, tab[i].pa);
}

int main()
{
    if(MyNodeId() > 0)
    {
        return 0;
    }

    wczytaj();
    punkty_artykulacji();

    printf("%lld\n", res);

    return 0;
}