栈的C语言实现

使用整型数组sta[SIZE]和整型变量top构成的结构体实现栈

栈的操作通过结构体指针实现

有如下功能：

1.栈空判断（isEmpty）

2.看栈顶（peek）

3.入栈（push）

4.出栈（pop）

5.销毁栈（destroy）

程序实现如下：

#include<stdio.h>
#include<string.h>//memset在其中

#define SIZE 10

struct stack
{
    int sta[SIZE];
	int top;
};

void init_stack(struct stack *s)//初始化栈
{
    memset(s->sta, 0, sizeof(s->sta)); 
	//memset为memory set 缩写，直接操作内存空间，memset(*p,int c,int n)意为将p所指的前n个字节的内存单元都用c填充
	s->top = -1; //空栈时栈顶为-1
}

int isEmpty(struct stack *s)//判断栈空
{
	if ((s->top) == -1)
		return 1;
	else
		return 0;
}

int peek(struct stack*s)//看栈顶
{
	if (isEmpty(s))
	{	
		printf("Stack is Empty!\n");
		return -1;
	}
	else 
		return ((s->sta)[s->top]);
}

int push(struct stack *s, int data)//入栈
{
	if(s->top == SIZE)
	{
		printf("The stack is full.\n");
		return 1;
	}
	(s->top)++;
	s->sta[s->top] = data;
	return 0;
} 

int pop(struct stack *s)//出栈
{
	int tmp;
	if(s->top == -1)
	{
		printf("The stack is empty.\n");
		return -1;
	}
	else
	{
		tmp = (s->sta)[s->top];
		(s->top)--;
		return tmp;
	}
}

void destroy(struct stack *s)//销毁栈
{
	s->top = -1;
	memset(s->sta,0,sizeof(s->sta));
}

void main()
{
	struct stack mystack;
    struct stack *p;
	int i;
	
	p = &mystack;

	init_stack(p);
    for(i = 0; i<=9; i++)
	{
		push(p,i);
		printf("%d已入栈\n",i);
	}

	printf("using peek get the number which in top is %d\n",peek(p));
	/*测试pop
	for(i = 0; i<=8; i++)
	{
		printf("%d already out\n",pop(p));
	}
    printf("using peek get the number which in top is %d\n",peek(p));
	printf("%d already out\n",pop(p));*/
    /*测试destroy
	destroy(p);
	printf("using peek get the number which in top is %d\n",peek(p));*/
	if (isEmpty(p))
	    printf("Stack is Empty!\n");
    else
		printf("NO,Stack isn't empty\n");
}

运行结果：