C언어 덱 구현

1 개요

C언어 덱 구현
#include <stdio.h>
#include <malloc.h>

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

typedef struct Deque {
    Node* front;
    Node* rear;
    int size;
} Deque;

Node* createNode(int data) {
    Node* newNode = (Node*)malloc(sizeof(Node));
    newNode->data = data;
    newNode->next = newNode->prev = NULL;
    return newNode;
}

Deque* createDeque() {
    Deque* dq = (Deque*)malloc(sizeof(Deque));
    dq->front = dq->rear = NULL;
    dq->size = 0;
    return dq;
}

int isEmpty(struct Deque* dq) {
    return (dq->front == NULL);
}

void insertFront(struct Deque* dq, int data) {
    struct Node* newNode = createNode(data);
    if (isEmpty(dq)) {
        dq->front = dq->rear = newNode;
    } else {
        newNode->next = dq->front;
        dq->front->prev = newNode;
        dq->front = newNode;
    }
    dq->size++;
}

void insertRear(struct Deque* dq, int data) {
    struct Node* newNode = createNode(data);
    if (isEmpty(dq)) {
        dq->front = dq->rear = newNode;
    } else {
        newNode->prev = dq->rear;
        dq->rear->next = newNode;
        dq->rear = newNode;
    }
    dq->size++;
}

void deleteFront(struct Deque* dq) {
    if (isEmpty(dq)) {
        printf("Deque is empty\n");
        return;
    }
    struct Node* temp = dq->front;
    dq->front = dq->front->next;
    if (dq->front == NULL) {
        dq->rear = NULL;
    } else {
        dq->front->prev = NULL;
    }
    free(temp);
    dq->size--;
}

void deleteRear(struct Deque* dq) {
    if (isEmpty(dq)) {
        printf("Deque is empty\n");
        return;
    }
    struct Node* temp = dq->rear;
    dq->rear = dq->rear->prev;
    if (dq->rear == NULL) {
        dq->front = NULL;
    } else {
        dq->rear->next = NULL;
    }
    free(temp);
    dq->size--;
}

int getFront(struct Deque* dq) {
    if (isEmpty(dq)) {
        printf("Deque is empty\n");
        return -1;
    }
    return dq->front->data;
}

int getRear(struct Deque* dq) {
    if (isEmpty(dq)) {
        printf("Deque is empty\n");
        return -1;
    }
    return dq->rear->data;
}

int size(struct Deque* dq) {
    return dq->size;
}

void printDeque(Deque* dq) {
    if (isEmpty(dq)) {
        printf("Deque is empty\n");
        return;
    }
    Node* current = dq->front;
    while (current != NULL) {
        printf("%d ", current->data);
        current = current->next;
    }
    printf("\n");
}

int main() {
    Deque* dq = createDeque();
    insertRear(dq, 10);
    insertRear(dq, 20);
    printDeque(dq); // 10 20 
    insertFront(dq, 5);
    insertFront(dq, 2);
    printDeque(dq); // 2 5 10 20 
    deleteFront(dq);
    deleteRear(dq);
    printDeque(dq); // 5 10 
}
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