双向栈的初始化，判空判满，入栈以及出栈的代码 用C语言实现

双向栈（也称为双端队列，Deque）允许在两端进行插入和删除操作。在C语言中，我们通常使用动态数组或者链表来实现它。这里是一个简单的链式双向栈的结构和基本操作的示例：

#include <stdlib.h>

typedef struct Node {
    int data;
    struct Node* prev;
    struct Node* next;
} StackNode;

typedef struct DStack {
    StackNode* top; // 栈顶指针
    StackNode* bottom; // 栈底指针
    int size; // 栈元素数量
} DStack;

// 初始化空栈
DStack* initDStack() {
    DStack* stack = (DStack*)malloc(sizeof(DStack));
    if (!stack) {
        printf("Memory allocation failed.\n");
        return NULL;
    }
    stack->top = stack->bottom = NULL;
    stack->size = 0;
    return stack;
}

// 判空
int isEmpty(DStack* stack) {
    return stack->top == NULL;
}

// 判满
int isFull(DStack* stack) {
    return stack->size == MAX_SIZE; // 假设MAX_SIZE是预设的最大容量
}

// 入栈（数据放在栈顶）
void push(DStack* stack, int value) {
    StackNode* newNode = (StackNode*)malloc(sizeof(StackNode));
    if (!newNode) {
        printf("Memory allocation failed.\n");
        return;
    }
    newNode->data = value;
    newNode->prev = stack->top;
    if (stack->top != NULL)
        stack->top->next = newNode;
    else
        stack->bottom = newNode;
    stack->top = newNode;
    stack->size++;
}

// 出栈（弹出栈顶元素）
int pop(DStack* stack) {
    if (isEmpty(stack)) {
        printf("Stack is empty.\n");
        return -1; // 返回错误码，表示栈为空
    }

    StackNode* poppedNode = stack->top;
    stack->top = stack->top->next;
    if (stack->top != NULL)
        stack->top->prev = NULL;
    else
        stack->bottom = NULL;
    free(poppedNode);
    stack->size--;
    return poppedNode->data;
}