Struktur Data : Implementasi Queue Menggunakan Linked List dalam Bahasa C

📋 Daftar Isi

Deklarasi Elemen Antrian

#include <stdio.h>
#include <stdbool.h>

struct node
{
    int data;
    struct node* next;
};
typedef struct node* item;

Struktur Queue

struct queue
{
    int count;
    item front;
    item rear;
};
typedef struct queue* antrian;

Inisialisasi Queue

void initialize(antrian q)
{
    q->count = 0;
    q->front = NULL;
    q->rear = NULL;
}

Fungsi Insert

void q_insert(antrian q, int value)
{
    item new_item;
    new_item = (item)malloc(sizeof(struct node));
    new_item->data = value;
    new_item->next = NULL;

    if(!isempty(q))
    {
        q->rear->next = new_item;
        q->rear = new_item;
    }
    else
    {
        q->rear = q->front = new_item;
    }

    q->count++;
}

Fungsi Remove

void q_remove(antrian q)
{
    item tmp;
    tmp = q->front;
    q->front = q->front->next;
    q->count--;
    free(tmp);
}

Fungsi Display

void display(antrian q)
{
    item n;
    n = q->front;
    if(q->front == NULL)
    {
        printf("\nQueue masih kosong\n");
    }
    else
    {
        while(n != NULL)
        {
            printf("%d\n", n->data);
            n = n->next;
        }
    }
}

Source Code Lengkap

#include <stdio.h>
#include <stdbool.h>

struct node
{
    int data;
    struct node* next;
};
typedef struct node* item;

struct queue
{
    int count;
    item front;
    item rear;
};
typedef struct queue* antrian;

void initialize(antrian q)
{
    q->count = 0;
    q->front = NULL;
    q->rear = NULL;
}

bool isempty(antrian q)
{
    return (q->rear == NULL);
}

void q_insert(antrian q, int value)
{
    item new_item;
    new_item = (item)malloc(sizeof(struct node));
    new_item->data = value;
    new_item->next = NULL;

    if(!isempty(q))
    {
        q->rear->next = new_item;
        q->rear = new_item;
    }
    else
    {
        q->rear = q->front = new_item;
    }

    q->count++;
}

void q_remove(antrian q)
{
    item tmp;
    tmp = q->front;
    q->front = q->front->next;
    q->count--;
    free(tmp);
}

void display(antrian q)
{
    item n;
    n = q->front;
    if(q->front == NULL)
    {
        printf("\nQueue masih kosong\n");
    }
    else
    {
        while(n != NULL)
        {
            printf("%d\n", n->data);
            n = n->next;
        }
    }
}

int main()
{
    antrian q;
    q = (antrian)malloc(sizeof(struct node));
    initialize(q);

    q_insert(q,10);
    q_insert(q,20);
    q_insert(q,30);
    q_insert(q,40);

    printf("Queue sebelum dequeue\n");
    display(q->front);
    q_remove(q);
    printf("Queue setelah dequeue\n");
    display(q->front);

    return 0;
}