modul 3

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

using namespace std;

    int front=-1;
    int rear=-1;
    int Max=5;

struct data
{
    int numb;
};

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

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

int main()
{
    data Data[5];
    int pil;

    do
    {
        system("cls");
        cout << "Pilihan !!!" << endl;
        cout << "1. Enqueue" << endl;
        cout << "2. Dequeue" << endl;
        cout << "3. Show" << endl;
        cout << "4. Exit" << endl;
        cout << "Masukkan pilihan = ";
        cin >> pil;

        switch (pil)
        {
        case 1:
            {
                if (isFull()==true)
                {
                    cerr << "Data penuh" << endl;
                }
                else
                {
                    if (front==-1)
                    {
                        front++;
                    }
                    rear++;
                    cout << "Masukkan angka = ";
                    cin >> Data[rear].numb;
                }
                system("pause");
                break;
            }
        case 2:
            {
                if (isEmpty()==true)
                {
                    cerr << "Data masih kosong" << endl;
                }
                else if (front==rear)
                {
                    Data[front].numb='\0';
                    front--;
                    rear--;
                    cout << "Data telah di hapus" << endl;
                }
                else
                {
                    for(int i=0;i<rear;++i)
                    {
                        Data[i]=Data[i+1];
                    }
                    Data[rear].numb='\0';
                    rear--;
                    cout << "Data telah di hapus" <<endl;
                }
                system("pause");
                break;
            }
        case 3:
            {
                if(isEmpty()==true)
                {
                   cout << "Data masih kosong!!!" << endl;
                }
                else
                {
                    for (int i=0;i<=rear;i++)
                    {
                        cout << "<- [ " << Data[i].numb << " ] ";
                    }
                    cout << endl;

                }


                system("pause");
                break;
            }
        case 4:
            {
                return 0;
            }
        default:
            {
                cerr << "Pilihan tidak ada" << endl;
                system("pause");
                break;
            }
        }
    }while(pil<=4);
}