#define _GLIBCXX_DEBUG
#include <bits/stdc++.h>
using namespace std;
#define rep0(n) for (int counter = 0; counter < (int)(n); counter++)
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define rep2(i, s, n) for (int i = s; i < (int)(n); i++)
#define rep3(i, s, n) for (int i = s; i > (int)(n); i--)
#define ALL(obj) obj.begin(), obj.end()
#define from1(obj) obj.begin() + 1, obj.end()
#define db(x) cerr << #x << ":" << (x) << " "
#define dbl(x) cerr << #x << ":" << (x) << "\n"
#define db2(x, y) cerr << #x << ":" << (x) << ", " << #y << ":" << (y) << " "
#define db2l(x, y) cerr << #x << ":" << (x) << ", " << #y << ":" << (y) << "\n"
#define dbl2(x, y) cerr << #x << ":" << (x) << "\n" << #y << ":" << (y) << "\n"
#define db3(x, y, z) cerr << #x << ":" << (x) << ", " << #y << ":" << (y) << " " << #z << ":" << (z) << " "
#define db3l(x, y, z) cerr << #x << ":" << (x) << ", " << #y << ":" << (y) << ", " << #z << ":" << (z) << "\n"
#define dbl3(x, y, z) cerr << #x << ":" << (x) << "\n" << #y << ":" << (y) << "\n" << #z << ":" << (z) << "\n"
#define dbp(p) cerr << #p << ":(" << p.first << ", " << p.second << ") "
#define dbpl(p) cerr << #p << ":(" << p.first << ", " << p.second << ")\n"
#define dbt3(t3) cerr << #t3 << ":(" << get<0>(t3) << ", " << get<1>(t3) << ", " << get<2>(t3) << ") "
#define dbt3l(t3) cerr << #t3 << ":(" << get<0>(t3) << ", " << get<1>(t3) << ", " << get<2>(t3) << ")\n"
#define dbt4(t4) cerr << #t4 << ":(" << get<0>(t4) << ", " << get<1>(t4) << ", " << get<2>(t4) << ", " << get<3>(t4) << ") "
#define dbt4l(t4) cerr << #t4 << ":(" << get<0>(t4) << ", " << get<1>(t4) << ", " << get<2>(t4) << ", " << get<3>(t4) << ")\n"
#define dbv(vec) cerr << #vec << ":{ "; for (auto e : vec) cerr << e << ", "; cerr << "}\n"
#define dbvp(vec) cerr << #vec << ":{ "; for (auto p : vec) cerr << "(" << p.first << ", " << p.second << "), "; cerr << "}\n"
#define dbvv(vv) cerr << #vv << ":{\n"; for (auto vec : vv) { cerr << "{ "; for (auto e : vec) cerr << e << ", "; cerr << "}\n"; } cerr << "}\n"
#define dbm(map) cerr << #map << ":{ "; for (auto p : map) cerr << "(" << p.first << ", " << p.second << "), "; cerr << "}\n"
#define YN(f) cout << (f ? "YES" : "NO") << "\n"
#define Yn(f) cout << (f ? "Yes" : "No") << "\n"
#define yn(f) cout << (f ? "yes" : "no") << "\n"
using ll = long long;
using vi = vector<int>; using vl = vector<ll>; using vs = vector<string>; using vb = vector<bool>;
using vvi = vector<vi>; using vvl = vector<vl>; using vvb = vector<vb>;
using pii = pair<int, int>; using pil = pair<int, ll> ; using pli = pair<ll, int>; using pll = pair<ll, ll>;
using vpii = vector<pii>; using vpll = vector<pll>;
using ti3 = tuple<int, int, int>; using tl3 = tuple<ll, ll, ll>;
using ti4 = tuple<int, int, int, int>; using tl4 = tuple<ll, ll, ll, ll>;
using mii = map<int, int>; using mil = map<int, ll>; using mli = map<ll, int>; using mll = map<ll, ll>;

vi par; // par[i]: 要素iの親
vi dep; // dep[i]: 要素iが根であるときは，iを含む木の最も深い要素の(根を0とした)深さ(rank)。iが根であるといえなければ dep[root(i)] とする。
vi siz; // siz[i]: 要素iが根であるときは，iを含む木の大きさ(要素数，size)。iが根であるといえなければ siz[find(i)] とする。

int root(int x) {
	if (par[x] == x) return x;
	else return par[x] = root(par[x]); // 縮約
}

void unite(int x, int y) {
	x = root(x); y = root(y);
	if (x == y) return;
	if (dep[x] > dep[y]) { // xを根とする木の方が深い場合
		par[y] = x; // xが根となる
		siz[x] += siz[y];
	} else if (dep[x] < dep[y]) {
		par[x] = y;
		siz[y] += siz[x];
	} else { // 深さが等しい場合，xを根とすることとする
		par[y] = x;
		dep[x] ++;
		siz[x] += siz[y];
	}
}

bool same(int x, int y) {
	return root(x) == root(y);
}

int main() {	// 0-ind，要素数N
	int N, M; cin >> N >> M;
	vpii e(M);
	rep(i, M) {
		int a, b; cin >> a >> b;
		e[i] = pii(--a, --b);		
	}
	int ans = 0;
	rep(i, M) { // 辺[i]を除いた場合のuniteの回数を数える。		
		par.assign(N, -1); dep.assign(N, 0); siz.assign(N, 1);
		rep(i, N) par[i] = i; // 全ての要素につき自身が根であるとして初期化
		int cnt = 0;
		rep(j, M) {
			if (j == i) continue;
			else {
				int a, b; tie(a, b) = e[j];
				if (!same(a, b)) {
					unite(a, b);
					cnt++;
				}
			}
		}
		if (cnt < N - 1) ans++;
		db(i); db(cnt); dbl(ans);
	}
	cout << ans << endl;
}

Measured memory_bytes: 256