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
import java.util.*;
import java.io.*;

public class B {
	
	public static void main(String[] args) throws IOException {
		FastScanner qwe = new FastScanner(System.in);
		
		int n = qwe.nextInt();
		int m = qwe.nextInt();
		
		ArrayList<Integer>[] aj = new ArrayList[n+1];
		for (int i = 0; i < aj.length; i++) {
			aj[i] = new ArrayList<Integer>();
		}
		
		ArrayDeque<Integer> dq = new ArrayDeque<>();
		
		boolean[] issingle = new boolean[n+1];
		Arrays.fill(issingle,true);
		boolean[] seen = new boolean[n+1];
		for(int i =0; i < m; i++){
			int a = qwe.nextInt();
			int b = qwe.nextInt();
			issingle[a]= false;
			issingle[b] = false;
			if(i ==0){
				dq.add(a);
				seen[a] = true;
			}
			
			aj[a].add(b);
			if(a != b)
				aj[b].add(a);
			
		}
		
		while(!dq.isEmpty()){
			int at = dq.poll();
			
			for(int to : aj[at]){
				if(!seen[to]){
					seen[to] =true;
					dq.add(to);
				}
			}
			
		}
		
		boolean impos = false;
		long ans = 0;
		for(int i =0; i < n; i++){
			if(!issingle[i] && !seen[i]) impos = true;
			
			long size = aj[i].size();
			ans += size*(size-1)/2;
			
			
		}
		
		if(impos) System.out.println("0");
		else System.out.println(ans);
		
		qwe.close();
	}
	
	static class FastScanner
	{
		BufferedReader br;
		StringTokenizer st;
		public FastScanner(InputStream in)
		{
			br = new BufferedReader(new InputStreamReader(in));
			st = new StringTokenizer("");
		}
		public String next() throws IOException
		{
			while(!st.hasMoreTokens()) st = new StringTokenizer(br.readLine());
			return st.nextToken();
		}
		public int nextInt() throws IOException
		{
			return Integer.parseInt(next());
		}
		public double nextDouble() throws IOException
		{
			return Double.parseDouble(next());
		}
		public void close() throws IOException
		{
			br.close();
		}
	}

}
