C语言链式栈

stack.h

typedef struct Node_s {
	int data;
	struct Node_s *pNext;
} Node_t, *pNode_t;

typedef struct Stack_s {
	pNode_t pHead;//栈顶指针，指向了链表的第一个结点
	int size;//栈的元素个数
} Stack_t, *pStack_t;

void init(pStack_t pStack);
void push(pStack_t pStack, int data);
int isEmpty(pStack_t pStack);
void pop(pStack_t pStack);
int top(pStack_t pStack);
int size(pStack_t pStack);

main.c

#define _CRT_SECURE_NO_WARNINGS
#include 
#include 
#include 
#include "stack.h"
int main() {
	Stack_t stack;
	init(&stack);
	for (int i = 0; i < 5; ++i) {
		push(&stack, i);
		printf("top = %d\n", top(&stack));
	}
	for (int i = 0; i < 6; ++i) {
		pop(&stack);
		printf("pop, top = %d\n", top(&stack));
	}
}
//初始化
void init(pStack_t pStack) {
	memset(pStack, 0, sizeof(Stack_t));
}
//压栈
void push(pStack_t pStack, int data) {
	pNode_t pNew = (pNode_t)calloc(1, sizeof(Node_t));
	pNew->data = data;
	//这个链表只有pHead没有pTail，所以不用判断是否为空
	pNew->pNext = pStack->pHead;
	pStack->pHead = pNew;
	++pStack->size;
}
//判空
int isEmpty(pStack_t pStack) {
	return pStack->size == 0;
}
//弹栈
void pop(pStack_t pStack) {
	if (isEmpty(pStack)) {
		fprintf(stderr, "Stack is empty!\n");
		return -1;
	}
	pNode_t pCur = pStack->pHead;
	pStack->pHead = pCur->pNext;
	free(pCur);
	pCur = NULL;
	--pStack->size;
}
//获取栈顶数据
int top(pStack_t pStack) {
	if (isEmpty(pStack)) {
		fprintf(stderr, "Stack is empty!\n");
		return -1;
	}
	return pStack->pHead->data;
}
//获取栈的大小
int size(pStack_t pStack) {
	return pStack->size;
}