Linear Elimination(inout(N,D,C)) // What does inout mean?
{
  Found_Strongly_connected(GF); // the function is try to find all the SCC of GF of                                     //   (N,D,C)
  for(m=1;m<number_SCC;m++)   // in each SCC?
  {
   SCC(m);
   substitution=i;            //choose any var i belong to SCC
   L=all_reachable(i); // directly, all_reachable(i) return a set that is     
     //  directly reachable from i.
   While(!empty(L))
     { j=reachable(i);
       delete(j);
       for(p=1;p<n_constraint(j)&&C!=C(j,i);p++)   //hoe to express except C(j,i)    
       {
         compose(i,j,k) ;
         update(C);
         modify(L);
        
       }
     }
 
  }
  for(n=1;n<n_eliminated;n++)
  {
   delete(eliminated);
   delete(edges);
  }
  o=topsort(left); // functional ??
  while(!empty(o))
  {
    i=first(o);
    delete(i);
    L=all_reachable(i);
    while(!empty(L))
      {
         j=reachable(i);
         delete(j);
         for(p=1;p<n_constraint(j)&&C!=C(j,i);p++)   //hoe to express except C(j,i)    
           {
             compose(i,j,k) ;
             update(GF);
             modify(L);
        
           }
      }
   
  }

}