堆栈

- 堆栈

*

堆栈的数组存储

1.定义

#define MaxSize
typedef struct SNode *Stack;
struct SNode{
        ElementType Data[MaxSize];
        int top;         //top是记录栈顶元素下标
}; 

2.push

void Push(Stack PtrS,ElementType item)
{
    if(Ptrs->top+1==MaxSize){
        printf(“堆栈满”);return;
    }else {
        PtrS->Data[++(Ptrs->top)]=item;        //执行两步操作，Ptrs->top的++，和赋值
        return;
    }
}

3.pop

ElementType Pop(Stack PtrS)
{
    if(PtrS->top==-1){
        printf(“堆栈空”);return ERROR;
    }else {
        return (PtrS->Data[(PtrS->top)--]);/        /执行两步操作，赋值，和Ptrs->top的--
}

4.两个堆栈的操作

数组的链式存储

• 注意：堆栈的链式存储top在头结点！！

1.定义

2.push

void Push(ElementType item,Stack S)
{
    struct SNode *TmpCell;
    TmpCell=(struct SNode*)malloc(sizeof(struct SNode));
    TmpCell->Data=item;
    Temp->Next=S->next;
    S->Next=TmpCell;        //S还是指向该链式栈头结点
}

3.pop

ElementType Pop(Stack S)
{
    struct SNode *FirstCell;
    ElementType TopElem;
    if(IsEmpty(S)){
        printf(“堆栈空”);return NULL;
    }else {
        FirstCell=S->Next;
        S->Next=FirstCell->Next;
        TopElem=FirstCell->Data;
        free(FirstCell);
        return TopElem;
}