Data structure - link stack

1. FIG link stack

And the same storage structure of the storage structure of the single chain link stack. As the stack is to delete and add elements in the top of the stack, therefore, the head of the list as the top of the stack is the most convenient. And there is no need to for simplicity as a single linked list operation as a first additional node.
Note that stack pointer in the chain direction is directed from the stack bottom of the stack .

// 链栈的存储结构
typedef struct StackNode
{
    int data;
    struct StackNode *next;
}StackNode,*LinkStack;

2. The link stack initialization

int InitStack(LinkStack &S)
{
	S=NULL;  //将栈顶指针置空
	return 1; 
}

3. The link stack into the stack (the stack is not necessary before determining whether the stack is full)

Algorithm steps
- 1, the space allocated for the stack element e, p pointer points.
- 2, the new node data field is set as e.
- 3, a new node is inserted into the stack.
- 4, to modify the stack pointer p
Algorithm Description

int Push(LinkStack &S,int e)
{
    //元素e入栈
    StackNode *p;
    p=new StackNode;  // 生成新节点
    p->data=e;        // 将新节点数据域置为e
    p->next=S;        // 将新节点插入栈顶
    S=p;              // 修改栈顶指针
    return 1；        //链栈要注意指针的方向是从栈顶指向栈底的 
}

4. The link stack pop

And a sequence of stack as link stack before the stack is also necessary to determine whether the stack is empty, except that the link stack after the stack needs to release the stack space of the stack elements .
Algorithm steps
- 1, it is determined whether the stack is empty, empty if ERROR is returned.
- 2, the top element is assigned to e.
- 3, the top element is temporarily save space, to prepare for release.
- 4, modify the stack pointer, points to the new top of the stack.
- 5, the top element of the original release of the space.
Algorithm Description

int Pop(LinkStack &S,int &e)
{
    if(S==NULL)
    {
        return 0;    // 栈空
    }
	
    e=S->data;      //将栈顶元素赋值给e
    StackNode *p;   
    p=S;              // 临时保存栈顶元素空间，准备释放
    S=S->next;     // 修改栈顶指针
    delete p;     // 释放原栈顶元素空间
    return 1;
}

5. Remove the top element

As with the sequence of stack, when the stack is not empty, the operation returns the value of the current top of the stack, stack pointer S remains unchanged.

int GetTop(LinkStack S)
{
    //返回S的栈顶元素,不修改栈顶指针
    if(S!=NULL)  // 栈非空
    return s->data;  // 返回栈顶元素的值,栈顶指针不变
}

6. code implementation

main.cpp

#include <iostream>

using namespace std;

// 链栈的存储结构
typedef struct StackNode
{
    int data;
    struct StackNode *next;
}StackNode, *LinkStack;

// 初始化
int InitStack(LinkStack &S) 
{
	S = NULL;   // 将栈顶指针置空
	return 1;
}

// 入栈
int Push(LinkStack &S, int e)
{
	//元素e入栈
	StackNode *p;
	p = new StackNode;  // 生成新节点
	
	p->data = e;        // 将新节点数据域置为e
	p->next = S;        // 将新节点插入栈顶
	S = p;             // 修改栈顶指针
	return 1;         // 链栈要注意指针的方向是从栈顶指向栈底的 
}

// 出栈
int Pop(LinkStack &S, int &e)
{
	if (S == NULL)
	{
		return 0;    // 栈空
	}
	e = S->data;    //将栈顶元素赋值给e
	StackNode *p;
	p = S;         // 临时保存栈顶元素空间，准备释放
	S = S->next;    // 修改栈顶指针
	delete p;     // 释放原栈顶元素空间
	return 1;
}

// 取栈顶元素
int GetTop(LinkStack S)
{
	//返回S的栈顶元素,不修改栈顶指针
	if (S != NULL)  // 栈非空
		return S->data;  // 返回栈顶元素的值,栈顶指针不变
}

void TraveStack(LinkStack S) 
{
	StackNode *p;
	p = S;
	while (p) 
	{
		printf("%d ", p->data);
		p = p->next;
	}
	printf("\n");
}

int main() 
{
	LinkStack S;

	if (InitStack(S)) 
	{
		printf("链栈初始化成功!\n");
	}
	else 
	{
		printf("链栈初始化失败!\n");
	}

	// 入栈
	int n;
	printf("请输入栈的元素个数:");
	scanf("%d",&n);
	for (int i = 0; i < n;)
	{
		int e;
		printf("请输入第%d个入栈的元素:",++i);
		scanf("%d", &e);
		Push(S, e);
	}
	printf("遍历栈:\n");
	TraveStack(S);

	// 出栈（取出两个元素）
	for (int i = 0; i < 2;)
	{
		int a;
		Pop(S, a);
		printf("第%d个出栈的元素:%d\n", ++i, a);
	}
	printf("遍历栈:\n");
	TraveStack(S);
	
	printf("栈顶元素是:%d\n", GetTop(S));
	
	system("pause");
	
	return 0;
}

operation result

Data structure - link stack

Guess you like