/*
 * stack.h
 */
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
typedef int (*CompareFuncT)(void*, void*);
struct StackNode{
  void *data;
  void *next;
  int rc;
};
typedef struct StackNode sNode;
struct Stack{
  sNode *top;
  sNode *bottom;
  CompareFuncT cf;
  int size;
};
typedef struct Stack* sPtr;
struct StackIterator{
  sNode *ptr;
};
typedef struct StackIterator* siPtr;
sPtr SCreate(CompareFuncT cf);
void SDestroy(sPtr s);
int SPush(sPtr s, void *data);
void *SPop(sPtr s);
int SDelete(sPtr s, void *data);
siPtr SCreateIterator(sPtr s);
void SDestroyIterator(siPtr si);
void *SAdvanceIterator(siPtr si);