cs231/28_circular queue using array.c at master · ceccs17d55/cs231 · 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
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
// Visakh Sebastian
// s3 d
// 55


#include <stdio.h>
#define size 10
int queue[size], front, rear;

void enqueue() {
	int data;
  if ((front == rear+1) || (front==0 && rear == size-1)) {
    printf("Queue overflow\n");
  } else {
		printf("Enter data to be entered : ");
		scanf("%d", &data);
    if (rear == -1) {
      rear = front = 0;
    } else {
      rear = (rear+1)%size;
    }
    queue[rear] = data;
  }
}
void dequeue() {
  if (front == -1) {
    printf("Queue underflow\n");
  } else {
    if (front == rear) {
      front = rear = -1;
    } else {
      front = (front+1)%size;
    }
  }
}
void printQueue() {
  int i=0;
  if (front<=rear) {
    for (i=0; i<front; i++) {
      printf("-:");
    }
    for (;i<=rear; i++) {
      printf("%d:", queue[i]);
    }
    for (;i<size; i++) {
      printf("-:");
    }
  } else {
    for (i=0; i<=rear; i++) {
      printf("%d:", queue[i]);
    }
    for (;i<front; i++) {
      printf("-:", queue[i]);
    }
    for (;i<size;i++) {
      printf("%d:", queue[i]);
    }
  }
}
int main() {
	char choice;
	front = rear = -1;
	do {
		printf("\n\tQueue using array\n1.Enqueue\n2.Dequeue\n3.Display\n4.Exit\nEnter your choice : ");
		scanf(" %c", &choice);
		switch(choice) {
			case '1':
				enqueue();
				break;
			case '2':
				dequeue();
				break;
			case '3':
				printQueue();
				break;
		}
	} while(choice != '4');
}
/*
Output
[?1h=$ ./28_circular_queue_using_array
[?1l>
	Queue using array
1.Enqueue
2.Dequeue
3.Display
4.Exit
Enter your choice : 1
Enter data to be entered : 1

	Queue using array
1.Enqueue
2.Dequeue
3.Display
4.Exit
Enter your choice : 1
Enter data to be entered : 2

	Queue using array
1.Enqueue
2.Dequeue
3.Display
4.Exit
Enter your choice : 1
Enter data to be entered : 3

	Queue using array
1.Enqueue
2.Dequeue
3.Display
4.Exit
Enter your choice : 4 5

	Queue using array
1.Enqueue
2.Dequeue
3.Display
4.Exit
Enter your choice : 3
1:2:3:-:-:-:-:-:-:-:
	Queue using array
1.Enqueue
2.Dequeue
3.Display
4.Exit
Enter your choice : 2

	Queue using array
1.Enqueue
2.Dequeue
3.Display
4.Exit
Enter your choice : 3
-:2:3:-:-:-:-:-:-:-:
	Queue using array
1.Enqueue
2.Dequeue
3.Display
4.Exit
Enter your choice : 4
*/