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#include <bits/stdc++.h>
#define pb push_back
#define ff first
#define ss second
const int N=200000;
const int M=500000;

using namespace std;

bool f[M];
int n,m,a,b,c,v[N],w;
vector <pair<int,int>> g[N];

int dfs(int a) {
	int w=1;
	v[a]=c;
	for (auto i: g[a]) {
		if (!f[i.ss] && v[i.ff]<c) {
			w+=dfs(i.ff);
		}
	}
	return w;
}

int main() {
	scanf("%d %d",&n,&m);
	for (int i=0; i<m; i++) {
		scanf("%d %d",&a,&b);
		g[a-1].pb({b-1,i});
		g[b-1].pb({a-1,i});
	}
	for (int i=0; i<m; i++) {
		f[i]=1;
		for (int j=i+1; j<m; j++) {
			f[j]=1;
			for (int k=j+1; k<m; k++) {
				f[k]=1;
				c++;
				if (dfs(0)<n) {
					w++;
				}
				f[k]=0;
			}
			f[j]=0;
		}
		f[i]=0;
	}
	printf("%d\n",w);
	return 0;
}