#include <stdio.h>

long v[4097];

int main()
 {
  freopen("triplete.in","r",stdin);
  freopen("triplete.out","w",stdout);

  register long i,j,k, n,m;
  long long T,T2=0;

  scanf("%ld%ld",&n,&m);

  T=n;
  T*=n-1;
  T/=2;
  T*=n-2;
  T/=3;

  for(i=1;i<=m;++i)
   {
    scanf("%ld%ld",&j,&k);
    ++v[j];
    ++v[k];
   }

  for(i=1;i<=n;++i)
   T2+=v[i]*(n-1-v[i]);

  T2/=2;
  T-=T2;
  printf("%lld\n",T);


  return 0;
 }