EDGE(PreDH 2021)

#include <iostream>
#include <cstdio>
#include <algorithm>
#include <vector>
#define task "edge"

using namespace std;
using ld = long double;
using ll = long long;

const int N = 1e5 + 5;
int n, m, low[N], num[N], l(0);
int cnt(0), brigde(0), dp[N];
ll ans(0);
vector<int> adj[N], x;

void Read()
{
    cin >> n >> m;

    for(int i = 1; i <= m; ++i)
    {
        int u, v;
        cin >> u >> v;

        adj[u].push_back(v);
        adj[v].push_back(u);
    }

}

void dfs(int v, int par = 0)
{
    low[v] = num[v] = ++l;

    dp[v] = 1;

    for(auto i : adj[v])
        if(i != par)
        {
            if(!num[i])
            {
                dfs(i, v);
                dp[v] += dp[i];

                low[v] = min(low[v], low[i]);

                if(low[i] > num[v]){
                    ans += 1ll * dp[i] * (n - dp[i]) - 1;
                    ++brigde;
                }
                else ans += 1ll * n * (n - 1) / 2 - m;
            }
            else {
                low[v] = min(low[v], num[i]);
                if(num[i] < num[v])
                    ans += 1ll * n * (n - 1) / 2 - m;
            }
        }
}

void Solve()
{
    for(int i = 1; i <= n; ++i)
        if(!num[i])
        {
            dfs(i);
            ++cnt;
            x.push_back(i);
        }

    /// special cases

    if(cnt > 2)
    {
        cout << 0;
        return;
    }
    else if(cnt == 2)
    {
        cout << (1ll * dp[x[0]] * dp[x[1]] * (m - brigde));
        return;
    }

    /// normal case

    cout << ans;
}

int32_t main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    if(fopen(task".INP", "r"))
    {
        freopen(task".INP", "r", stdin);
        freopen(task".OUT", "w", stdout);
    }

    Read();
    Solve();
}