#include <stdio.h>
#define NMAX 5000

int gr[NMAX];
int i, N, M;
long long Nr, Cnt;
int a, b;

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

     scanf("%d %d", &N, &M);

     Nr = (long long)N*(N-1)*(N-2)/6;

     for (i = 1; i <= M; i++)
     {
          scanf("%d %d", &a, &b);

          gr[a]++;
          gr[b]++;
     }

     for (i = 1; i <= N; i++) Cnt += (long long) gr[i]*(N - 1 - gr[i]);

     Cnt /= 2;

     printf("%lld\n", Nr - Cnt);

     return 0;
}