数据结构 中数制转换(栈的应用)

#include<stdio.h> 
#include<malloc.h> 
#include<stdlib.h> 
typedef struct Node 
{ 
 int data; 
 struct Node * pNext; 
}NODE ,*PNODE; 
typedef struct Stack 
{ 
 PNODE pTop; 
 PNODE pBottom; 
}STACK,*PSTACK; 
 
bool empty(PSTACK ps) 
{ 
 if(ps->pTop == ps->pBottom) 
 return true; 
 else return false; 
} 
void initstack(PSTACK ps) 
{ 
 ps->pTop=(PNODE)malloc(sizeof(NODE)); 
 if (NULL == ps->pTop) 
 { 
  printf("初始化失败！\n"); 
  exit(-1); 
 } 
 else 
 { 
 ps->pBottom=ps->pTop; 
 ps->pTop->pNext=NULL; 
 } 
 return ; 
} 
 
void push(PSTACK ps,int val) 
{ 
 PNODE pNew=(PNODE)malloc(sizeof(NODE)); 
 pNew->data=val; 
 pNew->pNext=ps->pTop; 
 ps->pTop=pNew; 
 return; 
} 
void pop(PSTACK ps) 
{ 
 int x; 
 if(empty(ps)) 
 { 
  //printf("出栈失败！"); 
  return ; 
 } 
 else 
 { 
   PNODE p=ps->pTop; 
   x=p->data; 
   ps->pTop=p->pNext; 
   free(p); 
   p=NULL; 
   printf("%d",x); 
   return ; 
 } 
} 
int main() 
{ 
 int i,N,B; 
 STACK S; 
 scanf("%d",&N); 
 scanf("%d",&B); 
 initstack(&S); 
 while(N) 
 { 
  push(&S,N%B); 
  N=N/B; 
 } 
 while(S.pBottom!=NULL) 
 { 
  pop(&S); 
   
 } 
 system("pause"); 
 return 0; 
}