c 语言 栈 算法,【数据结构与算法】(三) c 语言栈的简单实现

//

// main.c

// testStack

//

// Created by lan on 16/3/11.

// Copyright © 2016年 lan. All rights reserved.

//

#include

#include

#include

#include

typedef struct Node {

int data;

struct Node *pNext;

} NODE, * PNODE;

typedef struct Stack {

PNODE pTop;

PNODE pBottom;

} STACK, * PSTACK;

void init(PSTACK);

void push(PSTACK, int);

bool pop(PSTACK, int *); //如果栈为空，出栈失败

bool empty(PSTACK);

void traverse(PSTACK);

void cclear(PSTACK);

int main(int argc, const char * argv[]) {

STACK S;

int val;

init(&S); //初始化空栈

push(&S, 1); //压栈

push(&S, 2);

push(&S, 3);

push(&S, 4);

traverse(&S); //遍历输出

pop(&S, &val);

printf("出栈的值为 = %d\n", val);

traverse(&S);

printf("清空栈:\n");

cclear(&S);

traverse(&S);

return 0;

}

void init(PSTACK pS) {

pS->pTop = (PNODE) malloc(sizeof(NODE));

if (NULL == pS->pTop) {

printf("内存分配失败，程序退出！\n");

exit(-1);

}

pS->pBottom = pS->pTop;

pS->pTop->pNext = NULL; //pS->pBottom->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;

}

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 p = pS->pTop;

* pVal = p->data;

pS->pTop = p->pNext;

free(p);

p = NULL; // 别忘了

return true;

}

}

void traverse(PSTACK pS) {

printf("遍历栈: ");

PNODE p = pS->pTop;

while (p != pS->pBottom) {

printf("%d ", p->data);

p = p->pNext;

}

printf("\n");

return;

}

void cclear(PSTACK pS) {

if (empty(pS)) {

return;

}

PNODE p = NULL;

while (pS->pTop != pS->pBottom) {

p = pS->pTop;

pS->pTop = p->pNext;

free(p);

p = NULL;

}

}

输出结果：

遍历栈: 4 3 2 1

出栈的值为 = 4

遍历栈: 3 2 1

清空栈:

遍历栈:

Program ended with exit code: 0