Write a program to implement “QUEUE” using array. || BrownCodeIt

Data structure definition:-

 The data structure Node represents a single node in the linked list]

Structure Node

        (   data to hold the relevant data value in a Node,

            next that holds the address of the next Node      

       )      

Source Code:   

1. #include<conio.h>
2. #include<stdio.h>
3. #define max 5
4. int queue[max],front=0,rear=0;
5. int menu();
6. void enqueue();
7. void dequeue();
8. void display();
9. void main()
10. {
11. int ch;
12. clrscr();
13. printf("\nQueues using Arrays\n");
14. do
15. {
16.     ch=menu();
17.     switch(ch)
18.     {
19.     case 1: enqueue();
20.     break;
21.     case 2: dequeue();
22.     break;
23.     case 3: display();
24.     break;
25.     case 4: exit();
26.     break;
27.     default:printf("\n Please enter a valid choice!!");
28.     }
29. }while(1);
30. }
31.  
32. int menu()
33.     {
34.     int ch;
35.     printf("\n1.ENQUEUE \n2.DEQUEUE \n3.DISPLAY \n4.EXIT");
36.     printf("\nEnter your Choice:");
37.     scanf("%d",&ch);
38.     return ch;
39.     }
40.  
41. void enqueue()
42. {
43.     int element;
44.     if(rear==max)
45.     {
46.         printf("\nOverflow!!");
47.     }
48.     else
49.     {
50.         printf("\nEnter Element:");
51.         scanf("%d",&element);
52.         queue[rear++]=element;
53.         printf("\n %d Enqueued at %d",element,rear);
54.     }
55.  
56. }
57.  
58. void dequeue()
59. {
60.     if(rear==front)
61.     {
62.         printf("\nUnderflow!!");
63.     }
64.     else
65.     {
66.         front++;
67.         printf("\nElement is Dequeued from %d",front);
68.    }
69. }
70. void display()
71. {
72.     int i;
73.     if(front==rear)
74.     {
75.         printf("\nQueue is Empty!!!");
76.     }
77.     else
78.     {
79.         printf(" \n");
80.         for(i=front;i<max;i++)
81.         {
82.             printf(" | %d ",queue[i]);
83.         }
84.             printf("|");
85.     }
86. }

Output:

Queues using Arrays
 
1.ENQUEUE
2.DEQUEUE
3.DISPLAY
4.EXIT
Enter your Choice:1
 
Enter Element:12
 
 12 Enqueued at 1
1.ENQUEUE
2.DEQUEUE
3.DISPLAY
4.EXIT
Enter your Choice:1
 
Enter Element:23
 
 23 Enqueued at 2
1.ENQUEUE
2.DEQUEUE
3.DISPLAY
4.EXIT
Enter your Choice:
23 Enqueued at 2
1.ENQUEUE
2.DEQUEUE
3.DISPLAY
4.EXIT
Enter your Choice:1
 
Enter Element:34
 
 34 Enqueued at 3
1.ENQUEUE
2.DEQUEUE
3.DISPLAY
4.EXIT
Enter your Choice:1
 
Enter Element:45
 
 45 Enqueued at 4
1.ENQUEUE
2.DEQUEUE
3.DISPLAY
4.EXIT
Enter your Choice:1
 
Enter Element:56
 
 56 Enqueued at 5
1.ENQUEUE
2.DEQUEUE
3.DISPLAY
4.EXIT
Enter your Choice:2
 
Element is Dequeued from 1
1.ENQUEUE
2.DEQUEUE
3.DISPLAY
4.EXIT
Enter your Choice:2
 
Element is Dequeued from 2
1.ENQUEUE
2.DEQUEUE
3.DISPLAY
4.EXIT
Enter your Choice:3
 
 | 34  | 45  | 56 |
1.ENQUEUE
2.DEQUEUE
3.DISPLAY
4.EXIT
Enter your Choice: 4