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#include "bits/stdc++.h"
using namespace std;

using ll = long long;
using ull = unsigned long long;
using db = long double;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pdd = pair<db, db>;
using tiii = tuple<int, int, int>;
using str = string;

#define vt vector
#define pb push_back
#define eb emplace_back
#define ins insert
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define sz(x) (int)x.size()

#define mp make_pair
#define mt make_tuple
#define fi first
#define se second

const int MOD = 1e9 + 7;
const int maxN = 300000;
const int INFi = 2e9;
const ll INF = 4e18;

vt<int> graph[100000];
int colors[100000];
int cntwhite, cntblack;

int factorial(int x) {
    int result = 1;
    for (int i = 2; i <= x; ++i) result *= i;
    return result;
}

void dfs(int x) {
    for (int v : graph[x]) {
        if (!colors[v]) {
            if (colors[x] == 1) {
                colors[v] = 2;
                cntblack++;
            } else {
                colors[v] = 1;
                cntwhite++;
            }
            dfs(v);
        }
    }
}

void solve() {
    fill(colors, colors + 100000, 0);
    int n, m;
    cin >> n >> m;
    for (int i = 0; i < m; ++i) {
        int u, v;
        cin >> u >> v;
        u--;
        v--;
        graph[u].pb(v);
        graph[v].pb(u);
    }
    ll answ = 0;
    for (int i = 0; i < n; ++i) {
        if (!colors[i]) {
            cntwhite = 1;
            cntblack = 0;
            colors[i] = 1;
            dfs(i);
            if (cntwhite > 1) {
                answ += factorial(cntwhite) / 2 / factorial(cntwhite - 2);
            }
            if (cntblack > 1) {
                answ += factorial(cntblack) / 2 / factorial(cntblack - 2);
            }
        }
    }
    cout << answ;
}

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(NULL);
    // freopen("input.txt", "r", stdin);
    // freopen("output.txt", "w", stdout);
    int t = 1;
    // cin >> t;
    while (t--) {
        solve();
    }
    return 0;
}