#include<iostream.h>
#include<fstream.h>
main()
{
long n,m,a[1000][1000],i,j,k,p,s,d,v[500000],t;
fstream f("triplete.in",ios::in);
fstream g("triplete.out",ios::out);
f>>n; f>>m;
memset(a,0,sizeof(a));
i=1;
do{
   f>>k;f>>p;
   a[k][p]=1;
   a[p][k]=1;
   i++;
   }while(i<=m);
i=1;j=1;s=0;t=1;
do{
    do{
       k=1;s=0;
      do{
	  if((a[i][k]==a[k][j])&&(a[k][j]==a[i][j])&&(a[i][j]==1))s++;
	  k++;
	 }while(k<=n);
       v[t]=s;
       t++;
       j++;
      }while(j<=n);
   i++;j=i;
  }while(i<=n);
d=n*(n-1); d/=2; d+=n;
long max;
max=v[1];
i=1;
do{
   if(v[i]>max)max=v[i];
   i++;
   }while(i<=d);
g<<max;


return 0;
}