CFD Online Discussion Forums - adjacent cells (neighbor cells)

Hi,
I want to obtain the adjacent cells of a cell (cells connected to each nodes not only faces), I loop over all cells, check to see if a cell shares any nodes with the cell of interest, and save a array of the ones that do. But I found taht the array (neighbourcell[Ncell][NeighC] in code) doesn't contain all the adjacent cells and I don't know why, please help me, thanks!

Code:

#include "udf.h"

#define Ncell 100000 /*number of cells*/

#define NeighC 26 /*maximun number of adjacent cells*/

cell_t c1,c2,neighbourcell[Ncell][NeighC];

Thread *t;

int ii,jj,kk;

DEFINE_INIT(init,domain)

{

 for(ii=0;ii<Ncell;ii++)

  for(jj=0;jj<NeighC;jj++)

   neighbourcell[ii][jj]=-1;

 thread_loop_c(t,domain)

 {

  begin_c_loop(c1,t)/*loop_c1*/

  {

   kk=0;

   begin_c_loop(c2,t)

   {

    for(ii=0;ii<C_NNODES(c1,t);++ii)

     for(jj=0;jj<C_NNODES(c2,t);++jj)

      if(C_NODE(c1,t,ii)==C_NODE(c2,t,jj))/*share Node;*/

      {

       neighbourcell[c1][kk]=c2;

       kk++;

       break;

      }

    if(C_NODE(c1,t,ii)==C_NODE(c,t,jj)) break;/*exit loop_c1*/

   }

   end_c_loop(c2,t)

  }

  end_c_loop(c1,t)

 }

}