C基础--栈的静态和动态生成

main.c 文件

#include <stdio.h>
#include "stack.h"
int main(void)
{
    char *str = "abcdefghijklmn";

    init_stack(3);        //创建动态栈
    while (*str != ‘\0‘) {
        push(*str);
        str++;
    }
    while (is_empty() == 0)
        putchar(pop());
    putchar(‘\n‘);
    destory_stack();        //销毁动态栈

    return 0;
}

stack.c文件

#include <stdio.h>
#include <stdlib.h>
/*
static char stack[512] = {0};    //数据栈
static int top = 0;        //栈指针
void push(char ch)
{
    stack[top++] = ch;
}
char pop(void)
{
    return stack[--top];
}
int is_empty(void)
{
    return top == 0;
}
int is_full(void)
{
    return top == 512;
}
*/
static int sz = 512;
static char *stack;    //数据栈
static int top = 0;        //栈指针
void init_stack(int size)
{
    if (size == 0)
        size = sz;
    else
        sz = size;
    stack = (char *)malloc(sz);
}
void destory_stack(void)
{
    free(stack);
}
void push(char ch)
{
    if (top == sz)
    {
        sz += sz;
        stack = realloc(stack, sz);
    }
    stack[top++] = ch;
}
char pop(void)
{
    return stack[--top];
}
int is_empty(void)
{
    return top == 0;
}
int is_full(void)
{
    return top == sz;
}

stack.h文件

extern void push(char ch);
extern char pop(void);
extern int is_empty(void);
extern int is_full(void);
extern void init_stack(int size);
extern void destory_stack(void);