#include<cstdio>
using namespace std;
int n,m,x[100010],y[100010],i,j,k,ans[410],s[410][410];
int main()
{
	scanf("%d%d",&n,&m);
	for (i=1;i<=m;i++) scanf("%d%d",&x[i],&y[i]);
	for (i=1;i<=n;i++)
	{
		ans[i]=1;
		s[i][i]=1;
		for (j=m;j>=1;j--)//need to survive before the jth round?
		{
			if (s[i][x[j]]==0&&s[i][y[j]]==0) continue;
			if (s[i][x[j]]==1&&s[i][y[j]]==1) 
			{
				ans[i]=0;
				break;
			}
			s[i][x[j]]=1;s[i][y[j]]=1;
		}
	}
	int now=0;
	for (i=1;i<=n;i++)
	  for (j=i+1;j<=n;j++)
	  {
	  	if (ans[i]==0||ans[j]==0) continue;
	  	now++;
	  	for (k=1;k<=n;k++)
	  	  if (s[i][k]+s[j][k]>1)
	  	  {
	  	  	now--;
	  	  	break;
		  }
	  }
	printf("%d\n",now);
 } 