#include "bits/stdc++.h"
using namespace std;
#define ll long long
#define SZ(s) (int)s.size()
const int N = 1e5 + 5;
const int M = 1e9 + 7;
int n, m, h[N], p[N], sp[N][25];
ll ans;
vector <int> v[N];
void dfs(int x, int y) {
h[x] = h[y] + 1;
p[x] = y;
for(auto i : v[x]) {
if(i == y) continue;
dfs(i, x);
}
}
int lca(int x, int y) {
if(h[x] < h[y]) swap(x, y);
for(int i = 20; i >= 0; i--) {
if(h[sp[x][i]] >= h[y]) x = sp[x][i];
}
if(x == y) return x;
for(int i = 20; i >= 0; i--) {
if(sp[x][i] != sp[y][i]) x = sp[x][i], y = sp[y][i];
}
return p[x];
}
int f(int x, int y) {
return max(0, h[x] + h[y] - 2 * h[lca(x, y)] - 1);
}
int main() {
ios_base::sync_with_stdio(false); cin.tie(nullptr);
cin >> n >> m;
assert(m == n-1);
for(int i = 1; i <= m; i++) {
int u1, u2;
cin >> u1 >> u2;
v[u1].push_back(u2);
v[u2].push_back(u1);
}
dfs(1, 0);
for(int i = 1; i <= n; i++) {
sp[i][0] = p[i];
}
for(int j = 1; j <= 20; j++) {
for(int i = 1; i <= n; i++) {
sp[i][j] = sp[sp[i][j-1]][j-1];
}
}
for(int i = 1; i <= n; i++) {
for(int j = i+1; j <= n; j++) {
ans += f(i, j);
}
}
cout << ans * 2;
return 0;
}
