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<cstdio>
#include<cstring>
#include<cstdlib>
#include<cmath>
#include<iostream>
#include<algorithm>
using namespace std;
typedef long long ll;
const int MAXN=1000005;
int vis[MAXN],loop[MAXN];
vector<int>e[MAXN];
void dfs(int u)
{
    vis[u]=1;
    for(int i=0;i<(int)e[u].size();i++)
    {
        int v=e[u][i];
        if(!vis[v])dfs(v);
    }
}
int main()
{
    int n,m,lp=0;
    scanf("%d%d",&n,&m);
    for(int i=1;i<=m;i++)
    {
        int u,v;
        scanf("%d%d",&u,&v);
        if(u==v)loop[i]=1,lp++;
        else
        {
            e[u].push_back(v);
            e[v].push_back(u);
        }
    }
    for(int i=1;i<=n;i++)
        if(!e[i].empty() || loop[i])
        {
            dfs(i);
            break;
        }
    for(int i=1;i<=n;i++)
        if(!vis[i] && (!e[i].empty() || loop[i]))
            return 0*printf("0");
    ll res=0;
    for(int i=1;i<=n;i++)
    {
        int d=(int)e[i].size();
        res+=1LL*d*(d-1)/2;
    }
    res+=1LL*lp*(lp-1)/2;
    res+=1LL*lp*(m-lp);
    return 0*printf("%lld",res);
}