100 10
87 73
15 71
14 33
1 4
20 80
65 67
36 36
25 4
22 21
7 97
 4 2
3 3
3 4
 5 4
3 3
4 4
5 5
1 2
 4 4
1 2
2 3
3 1
4 4
 4 3
1 1
2 3
3 4
 1000000 1
255765 255765
 4 3
1 2
2 3
4 4
 4 2
1 1
1 2
 3 3
1 1
2 2
3 3
 5 4
1 1
2 3
2 4
2 5
 4 5
1 4
3 4
1 2
2 3
2 4
 4 4
2 3
2 4
3 4
4 4
 10 9
8 10
3 10
2 8
9 3
4 8
1 10
7 9
5 4
7 3
 10 10
1 2
2 3
3 4
4 5
5 1
6 6
7 7
8 8
9 9
10 10
 5 5
1 4
3 4
1 2
2 3
2 4
 3 3
1 2
2 2
3 3
 5 3
1 1
2 2
3 3
 6 12
1 2
1 3
2 3
1 1
2 2
3 3
4 5
5 6
4 6
4 4
5 5
6 6
 4 4
1 2
2 3
1 3
4 4
 5 4
1 2
3 3
4 4
5 5
 7 13
6 7
2 7
3 7
4 3
5 2
1 4
7 7
3 1
5 5
3 3
1 5
2 6
6 6
 2 2
1 1
2 2
 5 5
1 1
2 2
3 3
4 4
5 5
 1 1
1 1
 7 3
1 1
3 3
6 6
 3 3
1 1
2 3
3 3

0 1 0 0 0 0 0 1 0 0 8 6 12 0 8 0 0 0 0 0 57 0 0 0 0 0
#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e6 + 5;
int n, m;
vector<int> adj[maxn];
bool vis[maxn];
int selfloops[maxn];
long long totalSelfLoops = 0;
int dfs(int here) {
  vis[here] = true;
  int ret = adj[here].size();
  for (int i = 0; i < adj[here].size(); i++) {
    int there = adj[here][i];
    if (!vis[there]) ret += dfs(there);
  }
  return ret;
}
int gn = 1;
int main() {
  scanf("%d %d", &n, &m);
  for (int i = 0; i < m; i++) {
    int x, y;
    scanf("%d %d", &x, &y);
    if (x != y) {
      adj[x].push_back(y);
      adj[y].push_back(x);
    }
    if (x == y) {
      selfloops[x]++;
      totalSelfLoops++;
    }
  }
  for (int i = 1; i <= n; i++) {
    int x = dfs(i);
    if (x == 0)
      continue;
    else {
      if (x != 2 * m) {
        cout << 0 << endl;
        return 0;
      }
    }
  }
  long long ret = 0;
  for (int i = 1; i <= n; i++) {
    long long x = adj[i].size();
    ret += (x * (x - 1)) / 2;
  }
  for (int i = 1; i <= n; i++) {
    if (selfloops[i] > 0) {
      ret += m - totalSelfLoops;
    }
  }
  ret += (totalSelfLoops - 1) * totalSelfLoops / 2;
  cout << ret << endl;
  return 0;
}
