dst_lab/circularqueue.c at main · DIYA-BHATT29/dst_lab · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
#include<stdio.h>

int A[20],size,front,rear;
void ENQUEUE_CQ(int item)
{if((rear+1)%size==front)
printf("Queue is FULL. Insertion is not possible.");
else if(rear==-1)
{
front=0;
rear=0;
A[rear]=item;
}
else
{rear=(rear+1)%size;
A[rear]=item;
}
}
void DEQUEUE_CQ()
{
    if(front==-1)
printf("Queue is EMPTY");
 else if(front==rear)
{
    printf("Deleted item is %d", A[front]);
     front=-1;
     rear=-1;
}
else
{ printf("Deleted item is %d", A[front]);
 front=(front+1)%size;
}
}
void DEQUEUE_CQ()
{
if(front==-1)
printf("Queue is EMPTY");
else if(front==rear)
{ printf("Deleted item is %d", A[front]);
front=-1;
rear=-1;
}
else
{
printf("Deleted item is %d", A[front]);
front=(front+1)%size;
void DISPLAY_CQ()
 { int i;
if(front==-1)
printf("Queue is EMPTY");
else if(front<=rear)
{
     for(i=front;i<=rear;i++)
     printf("%d\t", A[i]);

}
else
 {for(i=front;i<=(size-1);i++)
 printf("%d\t", A[i]);
 for(i=0;i<=rear;i++)
 printf("%d\t", A[i]);
 }
 }
}

void main()
{
int item, opt;
front=-1;
rear=-1;
printf("Enter the size of the Queue: ");
scanf("%d", &size);
do
{
printf("\nEnter the option:\n");
printf("1.ENQUEUE\n2.DEQUEUE\n3.DISPLAY\n4.EXIT\n");
scanf("%d",&opt);
switch(opt)

{
     case 1: printf("Enter the item to be inserted: ");
      scanf("%d",&item);
       ENQUEUE_CQ(item);
       break;

case 2: DEQUEUE_CQ();
 break;

case 3: DISPLAY_CQ();
break;

case 4: break;

default: printf("Invalid option...");

}
}while(opt!=4);
}