链栈的C语言实现

typedef struct StackNode{
	int data;
	struct StackNode* next;
}LinkStack;

void Pop(LinkStack* lin)  
{
	int en;
	LinkStack* pn = (LinkStack*)malloc(sizeof(LinkStack));
	if (lin == NULL) { printf("ERROR.\n"); }
	else {
		if (pn) {
			en = lin->data;
			pn = lin;
			lin = lin->next;
			free(pn);
			printf("Element %d is poped out.\n", en);
		}
	}
	
}

void StackEmpty(LinkStack* lin) 
{ if (lin == NULL) 
	{ 
	printf("Empty.\n"); 
	} else { 
	printf("Not empty.\n"); 
	} 
}


void Push(LinkStack** lin)// Use second rand pointer to change the stack-top's position.
{
	int e = 0;
	LinkStack* p = (LinkStack*)malloc(sizeof(LinkStack));
	printf("Input the number you want to insert:\n");
	scanf_s("%d", &e);
	if ((*lin)->next != NULL) {
		if (p) {
			p->data = e;
			p->next = (*lin);
			(*lin) = p;
		}
	}
	else
	{
		(*lin)->data = e;
	}
}


void Pop(LinkStack** lin)  // Use second rand pointer to change the stack-top's position.
{
	int en;
	LinkStack* pn = (LinkStack*)malloc(sizeof(LinkStack));
	if ((*lin) == NULL) { printf("ERROR.\n"); }
	else {
		if (pn) {
			en = (*lin)->data;
			pn = (*lin);
			(*lin) = (*lin)->next;
			free(pn);
			printf("Element %d is poped out.\n", en);
		}
	}
	
}


void GetTop(LinkStack* lin)
{
	if (lin != NULL) {
		printf("The top element is: %d\n", lin->data);
	}
}

int main()
{
	LinkStack *Lst = (LinkStack*)malloc(sizeof(LinkStack));
	LinkStack** Lst1 = &Lst;
	Push(Lst1);// Input:1
	Push(Lst1);// Input:2
	GetTop(Lst);// Output:2
	Pop(Lst1);// Output:2
	Push(Lst1);// Input:3
	Push(Lst1);// Input:4
	GetTop(Lst);// Output:4
	Pop(Lst1);// Output:4
	GetTop(Lst);// Output:3
	Pop(Lst1);// Output:3
	Push(Lst1);// Input:5
	Pop(Lst1);// Output:5
	Pop(Lst1);// Output:1
	return 0;
}