circular queue using linked list in c 2b 2b

1#include<iostream>
2
3#define SIZE 100
4
5using namespace std;
6
7class node
8{
9public:
10    node()
11    {
12        next = NULL;
13    }
14  int data;
15  node *next;
16}*front=NULL,*rear=NULL,*n,*temp,*temp1;
17
18class cqueue
19{
20public:
21    void insertion();
22    void deletion();
23    void display();
24};
25
26int main()
27{
28    cqueue cqobj;
29  int ch;
30  do
31  {
32     cout<<"\n\n\tMain Menu";
33     cout<<"\n##########################";
34     cout<<"\n1. Insert\n2. Delete\n3. Display\n4. Exit\n\nEnter Your Choice: ";
35     cin>>ch;
36     switch(ch)
37     {
38        case 1:
39          cqobj.insertion();
40          cqobj.display();
41          break;
42        case 2:
43          cqobj.deletion();
44          break;
45        case 3:
46          cqobj.display();
47          break;
48        case 4:
49          break;
50        default:
51          cout<<"\n\nWrong Choice!!! Try Again.";
52     }
53  }while(ch!=4);
54  return 0;
55}
56
57void cqueue::insertion()
58{
59  n=new node[sizeof(node)];
60  cout<<"\nEnter the Element: ";
61  cin>>n->data;
62  if(front==NULL)
63  {
64      front=n;
65  }
66  else
67  {
68      rear->next=n;
69  }
70  rear=n;
71  rear->next=front;
72}
73
74void cqueue::deletion()
75{
76  int x;
77  temp=front;
78  if(front==NULL)
79  {
80      cout<<"\nCircular Queue Empty!!!";
81  }
82  else
83  {
84     if(front==rear)
85     {
86       x=front->data;
87       delete(temp);
88       front=NULL;
89       rear=NULL;
90     }
91     else
92     {
93        x=temp->data;
94        front=front->next;
95        rear->next=front;
96        delete(temp);
97     }
98     cout<<"\nElement "<<x<<" is Deleted";
99     display();
100  }
101}
102
103void cqueue::display()
104{
105  temp=front;
106  temp1=NULL;
107  if(front==NULL)
108  {
109    cout<<"\n\nCircular Queue Empty!!!";
110  }
111  else
112  {
113    cout<<"\n\nCircular Queue Elements are:\n\n";
114    while(temp!=temp1)
115    {
116       cout<<temp->data<<"  ";
117       temp=temp->next;
118       temp1=front;
119    }
120  }
121}