C语言数据结构——栈

C语言数据结构——栈

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#define MAXSIZE 100

typedef int ElemType; 

typedef struct{
	ElemType *data;
	int top;
}Stack;
//定义栈

Stack* initStack()
{
	Stack *s = (Stack*)malloc(sizeof(Stack));
	s->data = (ElemType*)malloc(sizeof(ElemType) * MAXSIZE);
	s->top = -1;
	return s;
}
//初始化

int isEmpty(Stack *s)
{
	if(s->top == -1)
	{
		printf("Empty.\n");
		return 1;
	}
	else
	{
		return 0;
	}
}
//确认栈是否为空

int push(Stack *s,ElemType e)
{
	if(s->top >= MAXSIZE - 1)
	{
		printf("Full.\n");
		return 0;
	}
	s->top++;
	s->data[s->top] = e;
	return 1;
} 
//压栈

ElemType pop(Stack *s,ElemType *e)
{
	if(s->top == -1)
	{
		printf("Empty.\n");
		return 0;
	}
	*e = s->data[s->top];
	s->top--;
	return 1;
}
//出栈

int getTop(Stack *s,ElemType *e)
{
	if(s->top == -1)
	{
		printf("Empty.\n");
		return 0;
	}
	*e = s->data[s->top];
	return 1;
} 
//获取栈顶元素

int main()
{
	Stack *s;
	s=initStack();
	push(s,10);
	push(s,20);
	push(s,30);
	ElemType e;
	pop(s,&e);
	printf("%d\n", e);
	getTop(s, &e);
	printf("%d\n", e);
	return 0;
}