kruskal.c:

. . .

main()
{

. . .

qsort(edgeTab,numEdges,sizeof(edgeType),weightAscending);
for (i=0;i<numEdges;i++)
{
  root1=find(edgeTab[i].tail);
  root2=find(edgeTab[i].head);
  if (root1==root2)
    printf("%d %d %d discarded\n",edgeTab[i].tail,edgeTab[i].head,
      edgeTab[i].weight);
  else
  {
    printf("%d %d %d included\n",edgeTab[i].tail,edgeTab[i].head,
      edgeTab[i].weight);
    makeEquivalent(root1,root2);
  }
}
if (numTrees!=1)
  printf("MST does not exist\n");
}

kruskalDup.c:

. . .

main()
{

. . .

qsort(edgeTab,numEdges,sizeof(edgeType),weightAscending);
i=0;
while (i<numEdges)
{
  for (k=i;
       k<numEdges && edgeTab[k].weight==edgeTab[i].weight;
       k++)
    ;
  for (j=i;j<k;j++)
  {
    root1=find(edgeTab[j].tail);
    root2=find(edgeTab[j].head);
    if (root1==root2)
    {
      printf("%d %d %d discarded\n",edgeTab[j].tail,edgeTab[j].head,
        edgeTab[j].weight);
      edgeTab[j].weight=(-1);
    }
  }
  for (j=i;j<k;j++)
    if (edgeTab[j].weight!=(-1))
    {
      root1=find(edgeTab[j].tail);
      root2=find(edgeTab[j].head);
      if (root1==root2)
        printf("%d %d %d alternate\n",edgeTab[j].tail,edgeTab[j].head,
          edgeTab[j].weight);
      else
      {
        printf("%d %d %d included\n",edgeTab[j].tail,edgeTab[j].head,
          edgeTab[j].weight);
        makeEquivalent(root1,root2);
      }
    }
  i=k;
}
if (numTrees!=1)
  printf("MST does not exist\n");
}