int compare(const Cell* A, const Cell* B)
{
if(A == NULL) {
if(B == NULL) return 0;
else return -1;
}
else if(B == NULL) return 1;
else if(A->item < B->item) return -1
else if(A->item > B->item) return 1
else return compare(A->next, B->next);
}