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#include <cstdio>
#include <iostream>
#include <algorithm>
#include <cstring>
#include <vector>
#include <set>
#include <map>
#include <array>
#include <random>
#include <cmath>
#include <list>
#include <ctime>
#include <sstream>
#include <queue>
#include <climits>
#include <stack>
#include <random>
#include <bitset>
#include <numeric>
#include <cassert>
using namespace std;
typedef vector<int> vi;
typedef pair<int,int> pii;
typedef long long ll;
#define rep(x, b, e) for(int x=(b); x<(e); ++x)
#define trav(a, x) for(auto& a : x)
#define ford(x, b, e) for(int x=((int)(b))-1; x>=(e); --x)
#define all(c) c.begin(),c.end()
#define sz(x) ((int)((x).size()))
#define pb push_back
#define st first
#define nd second
#define mp(x,y) make_pair(x,y)
typedef short int sint;

#define imie(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "

const int N = 502020;
vector<pii> za[N];
bool blocked[N];
vi seen;
vi visited;
int n, m;
int cnter;

void vis(int v) {
	visited[cnter++] = v;
	seen[v] = true;
	trav(ed, za[v]) {
		if (blocked[ed.nd]) {
			continue;
		}
		if (seen[ed.st]) {
			continue;
		}
		vis(ed.st);
	}
}

bool rozw() {
	cnter = 0;
	int st = rand() % n;
	vis(st);
	rep(i, 0, cnter) {
		seen[visited[i]] = false;
	}
	return cnter < n;
}

int main() {
	ios_base::sync_with_stdio(false); cin.tie(0);
	scanf("%d %d", &n, &m);
	rep(i, 0, m) {
		int x, y;
		scanf("%d %d", &x, &y);
		--x, --y;
		za[x].pb(mp(y, i));
		za[y].pb(mp(x, i));
	}
	seen.resize(n, 0);
	visited.resize(n, 0);
	int res = 0;
	rep(i, 0, m) {
		rep(j, i+1, m) {
			rep(k, j+1, m) {
				blocked[i] = blocked[j] = blocked[k] = true;
				if (rozw()) {
					++res;
				}
				blocked[i] = blocked[j] = blocked[k] = false;
			}
		}
	}
	printf("%d\n", res);
}