no :of nodes

Dear all,

How good is this function which is used to find  the no: of nodes
in each level of the binary tree. ?


int arrlev[100];

void preorder(struct btree *n,int lev)
{
       if(!(n))
       return;

       arrlev[lev]++;
       lev++;

      preorder(n->left,lev);
      preorder(n->right,lev);
}