#include <stdio.h>#include <malloc.h>#include <stdlib.h>#include <stdbool.h> typedef struct Node{ int data; struct Node * pNext;}NODE, * PNODE; typedef struct Stack{ PNODE pTop; PNODE pBottom;}STACK, * PSTACK; //PSTACK等價于struct STACK * void init(PSTACK); //初始化棧void push(PSTACK, int ); //壓棧void traverse(PSTACK); //遍歷bool pop(PSTACK pS,int * pVal); //出棧void clear(PSTACK pS); //清空棧 int main(void){ STACK S; //STACK等價于struct Stack int val; init(&S); //造出空棧  push(&S, 1); //壓棧 push(&S, 2); push(&S, 3); push(&S, 4); push(&S, 5); push(&S, 6);  traverse(&S); //遍歷輸出/* if(pop(&S,&val)) { printf("出棧成功，出棧的元素是%d/n", val); } else { printf("出棧失??！/n"); }*/  clear(&S); traverse(&S);  return 0;} void init(PSTACK pS){ pS->pTop = (PNODE)malloc(sizeof(NODE)); if(NULL == pS->pTop) { printf("動態內存分配失敗/n"); exit(-1); } else { pS->pBottom = pS->pTop; pS->pTop->pNext = NULL; }} void push(PSTACK pS, int val){ PNODE pNew = (PNODE)malloc(sizeof(NODE)); //創建新的節點 pNew->data = val; //將val的值賦給新節點的數據域 pNew->pNext = pS->pTop; //將新節點的指針域指向下一個節點.pS->Top不能改寫成pS->Bottom pS->pTop = pNew; //pTop指向新節點 return;} void traverse(PSTACK pS){ PNODE p = pS->pTop; while(p != pS->pBottom) { printf("%d ", p->data); p = p->pNext; } printf("/n"); return;} bool empty(PSTACK pS){ if(pS->pTop == pS->pBottom) { return true; } else { return false; }} bool pop(PSTACK pS,int * pVal){ if(empty(pS)) { return false; } else { PNODE r = pS->pTop; *pVal = r->data; pS->pTop = r->pNext; free(r); r = NULL; return true; }} //清空棧void clear(PSTACK pS){ if(empty(pS)) //如果 { return; } else { PNODE p = pS->pTop; //定義元素p指向棧頂元素 PNODE q = NULL； //定義元素q，初始值為空   while(p !=pS->pBottom) //如果棧不為空 {  q = p->pNext; //q指向p的下一個元素  free(p);  //釋放p所指向的棧頂元素  p = q;  //將q所指向的元素賦給p } pS->pTop = pS->pBottom;  }}