#pragma GCC optimize ("O3")
#pragma GCC target ("avx")
#include "bits/stdc++.h" // define macro "/D__MAI"

using namespace std;
typedef long long int ll;

#define xprintf(fmt,...) fprintf(stderr,fmt,__VA_ARGS__)
#define debugv(v) {printf("L%d %s > ",__LINE__,#v);for(auto e:v){cout<<e<<" ";}cout<<endl;}
#define debuga(m,w) {printf("L%d %s > ",__LINE__,#m);for(int x=0;x<(w);x++){cout<<(m)[x]<<" ";}cout<<endl;}
#define debugaa(m,h,w) {printf("L%d %s >\n",__LINE__,#m);for(int y=0;y<(h);y++){for(int x=0;x<(w);x++){cout<<(m)[y][x]<<" ";}cout<<endl;}}
#define ALL(v) (v).begin(),(v).end()
#define repeat(cnt,l) for(auto cnt=0ll;(cnt)<(l);++(cnt))
#define iterate(cnt,b,e) for(auto cnt=(b);(cnt)!=(e);++(cnt))
#define MD 1000000007ll
#define PI 3.1415926535897932384626433832795
#define EPS 1e-12
template<typename T1, typename T2> ostream& operator <<(ostream &o, const pair<T1, T2> p) { o << "(" << p.first << ":" << p.second << ")"; return o; }
template<typename iterator> inline size_t argmin(iterator begin, iterator end) { return distance(begin, min_element(begin, end)); }
template<typename iterator> inline size_t argmax(iterator begin, iterator end) { return distance(begin, max_element(begin, end)); }
template<typename T> T& maxset(T& to, const T& val) { return to = max(to, val); }
template<typename T> T& minset(T& to, const T& val) { return to = min(to, val); }

mt19937_64 randdev(8901016);
inline ll rand_range(ll l, ll h) {
    return uniform_int_distribution<ll>(l, h)(randdev);
}

#ifdef __MAI
#define getchar_unlocked getchar
#define putchar_unlocked putchar
#endif
#ifdef __VSCC
#define getchar_unlocked _getchar_nolock
#define putchar_unlocked _putchar_nolock
#endif
namespace {
#define isvisiblechar(c) (0x21<=(c)&&(c)<=0x7E)
    class MaiScanner {
    public:
        template<typename T> void input_integer(T& var) {
            var = 0;
            T sign = 1;
            int cc = getchar_unlocked();
            for (; cc<'0' || '9'<cc; cc = getchar_unlocked())
                if (cc == '-') sign = -1;
            for (; '0' <= cc&&cc <= '9'; cc = getchar_unlocked())
                var = (var << 3) + (var << 1) + cc - '0';
            var = var*sign;
        }
        inline int c() { return getchar_unlocked(); }
        inline MaiScanner& operator>>(int& var) {
            input_integer<int>(var);
            return *this;
        }
        inline MaiScanner& operator>>(long long& var) {
            input_integer<long long>(var);
            return *this;
        }
        inline MaiScanner& operator>>(string& var) {
            int cc = getchar_unlocked();
            for (; !isvisiblechar(cc); cc = getchar_unlocked());
            for (; isvisiblechar(cc); cc = getchar_unlocked())
                var.push_back(cc);
            return *this;
        }
        template<typename IT> void in(IT begin, IT end) {
            for (auto it = begin; it != end; ++it) *this >> *it;
        }
    };
}
MaiScanner scanner;


// 隣接頂点を保持する無向グラフ
class Graph {
public:
    size_t n;
    vector<vector<int>> vertex_to;

    Graph(size_t n) :n(n), vertex_to(n) {}

    void connect(int from, int to) {
        vertex_to[from].emplace_back(to);
        vertex_to[to].emplace_back(from);
    }
    void resize(size_t _n) {
        n = _n;
        vertex_to.resize(_n);
    }
};

void detect_articulation_point(const Graph& graph, vector<int>& out) {
    out.resize(graph.n);
    fill(out.begin(), out.end(), 0);
    vector<int> visited(graph.n);

    int cnt = 1;
    function<int(int)> dfs = [&](int idx) {
        //printf("%d: called %d\n",idx,visited[idx]);
        int p = visited[idx];
        for (int to : graph.vertex_to[idx]) {
            if (visited[to]) {
                p = min(p, visited[to]);
            }
            else {
                visited[to] = ++cnt;
                int q = dfs(to);
                if (visited[idx] == q) out[idx] = 1;
                p = min(p, q);
            }
        }
        //printf("%d: return %d\n",idx,p);
        return p;
    };
    visited[0] = 1;
    int start_degree = 0;
    for (int to : graph.vertex_to[0]) {
        if (!visited[to]) {
            ++start_degree;
            visited[to] = ++cnt;
            dfs(to);
        }
    }
    if (2 <= start_degree) out[0] = 1;
}

ll m, n, kei;

vector<pair<int, int>> edges;

int main() {

    scanner >> n >> m;

    //Graph g(n);

    repeat(i, m) {
        int a, b;
        scanner >> a >> b;
        --a; --b;
        //g.connect(a, b);
        edges.emplace_back(a, b);
    }

    // vector<int> res;
    // detect_articulation_point(g, res);
    // 
    // debugv(res);
    //
    //int ans = 0;
    //for (auto e : edges) {
    //    ans += ((res[e.first] || g.vertex_to[e.first].size() == 1) &&
    //        (res[e.second] || g.vertex_to[e.second].size() == 1));
    //}
    //cout << ans << endl;

    int ans=0;
    repeat(i, m) {
        Graph g(n);
        repeat(j, m)
            if (i != j)
                g.connect(edges[j].first, edges[j].second);
        
        vector<int> visited(n);
        function<void(int)> dfs = [&](int idx) {
            visited[idx] = 1;
            for (int to : g.vertex_to[idx])
                if (!visited[to])
                    dfs(to);
        };
        dfs(0);

        ans += n != accumulate(ALL(visited), 0);
    }
    cout << ans << endl;

    return 0;
}

Measured memory_bytes: 256