tugas tambahan modul 3

#include <iostream>
#include <stdlib.h>

using namespace std;

struct merk
{
    string namaMerk;
    int stock;
};

struct data
{
    string namaBarang;
    string deskripsiBarang;
    int harga;
    merk merkBarang;
    data *next;
    data *prev;
};

data *bantu,*baru,*awal=NULL,*akhir=NULL;
int front=-1,rear=-1,maks;

void inputData();
void deleteData();
void showData();
void enqueue();
void deque();
bool isFull();
bool isEmpty();

int main()
{
    char prompt;
    int pil;

    cout << "Masukkan jumlah maksimal antrian = ";
    cin >> maks;

    do
    {
        system("cls");
        cout << "Total data = " << rear+1 << endl;
        cout << "\nPilihan!!!" << endl;
        cout << "1. Input data" << endl;
        cout << "2. Show data" << endl;
        cout << "3. Delete data" << endl;
        cout << "4. Selesai" << endl;

        cout << "\n\nMasukkan pilihan = ";
        cin >> pil;

        switch(pil)
        {
        case 1:
            {
                enqueue();
                system("pause");
                break;
            }
        case 2:
            {
                showData();
                system("pause");
                break;
            }
        case 3:
            {
                deque();
                system("pause");
                break;
            }
        case 4:
            {
                return 0;
            }
        default:
            {
                cerr << "\n\nError : invalid input" << endl;
            }
        }
    }while (pil<=4);

    return 0;
}


void inputData()
{
    baru=new data;
    cout << "\nMasukkan nama barang = ";
    cin >> baru->namaBarang;
    cout << "Masukkan deskripsi barang = ";
    cin >> baru->deskripsiBarang;
    cout << "Masukkan merk barang = ";
    cin >> baru->merkBarang.namaMerk;
    cout << "Masukkan jumlah barang yang tersedia = ";
    cin >> baru->merkBarang.stock;
    cout << "Masukkan harga barang = ";
    cin >> baru->harga;
    baru->next=baru->prev=NULL;

    if (awal==NULL)
    {
        awal=akhir=baru;
    }
    else
    {
        akhir->next=baru;
        baru->prev=akhir;
        akhir=baru;
    }
}

void deleteData()
{
    if (awal==akhir)
    {
        delete awal;
        awal=akhir=NULL;
    }
    else
    {
        bantu=awal->next;
        bantu->prev=NULL;
        delete awal;
        awal=bantu;
    }
}

void showData()
{
    baru=awal;
    while(baru!=NULL)
    {
        cout << "\nNama barang = " << baru->namaBarang;
        cout << "\nDeskripsi barang = " << baru->deskripsiBarang;
        cout << "\nMerk barang = " << baru->merkBarang.namaMerk;
        cout << "\nJumlah barang yang tersedia = " << baru->merkBarang.stock;
        cout << "\nHarga barang = " << baru->harga << endl;
        cout << endl;
        baru=baru->next;
    }
}

bool isFull()
{
    if (rear+1==maks)
    {
        return true;
    }
    else
    {
        return false;
    }
}

bool isEmpty()
{
    if (rear==-1)
    {
        return true;
    }
    else
    {
        return false;
    }
}

void enqueue()
{
    if (isFull()==true)
    {
        cerr << "Error : Data sudah penuh!" << endl;
    }
    else
    {
        if (front==-1)
        {
            front++;
        }
        inputData();
        rear++;
    }
}

void deque()
{
    if (isEmpty()==true)
    {
        cerr << "Error : Data masih kosong!" << endl;
    }
    else if (front==rear)
    {
        deleteData();
        front--;
        rear--;
    }
    else
    {
        deleteData();
        rear--;
    }
}