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>
int n, m, sz, first[1000010], next[2000010], tail[2000010], vis[1000010],
    q[1000010];
void addedge(int u, int v);
int main(void) {
  scanf("%d%d", &n, &m);
  memset(first, 0, sizeof(first));
  int i, u, v;
  for (sz = 0, i = 1; i <= m; i++) {
    scanf("%d%d", &u, &v);
    addedge(u, v);
    addedge(v, u);
  }
  memset(vis, 0, sizeof(vis));
  int front = 1, rear = 1, e;
  vis[1] = 1;
  q[1] = 1;
  while (front <= rear) {
    u = q[front++];
    for (e = first[u]; e; e = next[e]) {
      v = tail[e];
      if (vis[v]) continue;
      vis[v] = 1;
      q[++rear] = v;
    }
  }
  for (i = 1; i <= n; i++)
    if (!vis[i]) break;
  if (i <= n)
    printf("0\n");
  else
    printf("%I64d\n", (long long)m * (m - 1) / 2);
  return 0;
}
void addedge(int u, int v) {
  tail[++sz] = v;
  next[sz] = first[u];
  first[u] = sz;
}
