C-Program-to-implement-Queue-using-Array/Queue.c at main · Mukish45/C-Program-to-implement-Queue-using-Array · 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
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
#include<stdio.h>
#define N 10

int queue[N];
int front = -1;
int rear = -1;

int enqueue();
int dequeue();
void size();
void frontElement();
void display();
void printline();

void main()
{
    int c;
    do
    {
        printline();
        printf("\nEnter  1.Enqueue  2.Dequeue  3.Size  4.Front Element   5. Display  6.Stop:\t");
        scanf("%d", &c);
        printline();
        switch (c)
        {
        case 1:
            enqueue();
            break;
        case 2:
            dequeue();
            break;
        case 3:
            size();
            break;
        case 4:
            frontElement();
            break;
        case 5:
            display();
            break;
        case 6:
            printf("\nExit!!!\n");
            printline();
            break;
        default:
            printf("\nInvalid entry!!!\n");
            printline();
        }
    }
    while(c!=6);
}

int enqueue()
{
    if(rear > N-1)
    {
        printf("\nOverflow condition\n");
        printline();
    }
    else if(rear ==-1 && front ==-1)
    {
        int a;
        rear++;
        front++;
        printf("\nEnter the element:\t");
        scanf("%d", &a);
        queue[rear] = a;
        rear++;
        printline();
    }
    else
    {
        int b;
        printf("\nEnter the element:\t");
        scanf("%d", &b);
        queue[rear] = b;
        rear++;
        printline();
    }
}

int dequeue()
{
    if(front == -1 && rear == -1)
    {
        printf("\n\t\tUnderflow condition\n");
        printline();
    }
    else if(front > N-1)
    {
        printf("\n\t\tAll the elements are dequeued\n");
        printline();
    }
    else if(front > rear)
    {
        printf("\nAll the entered elements in the queue are dequeued. Please Enqueue\n");
    }
    else
    {
        printf("\n\t\tThe dequeued element is %d",queue[front]);
        front++;
        printline();
    }
}

void size()
{
    if(front==-1 && rear==-1)
    {
        printf("\n\t\tUnderflow condition\n");
        printline();
    }
    else if(front>N-1 || front == rear)
    {
        printf("\n\t\tThe queue elements are dequeued\n");
        printline();
    }
    else
    {
        int x;
        x = rear - front;
        printf("\n\t\tThe size of the queue is %d",x);
        printline();
    }
}

void frontElement()
{
    if(front==-1 && rear==-1)
    {
        printf("\n\t\tUnderflow Condition\n");
        printline();
    }
    else if(front>N-1 || front == rear)
    {
        printf("\n\t\tThe queue elements are dequeued\n");
        printline();
    }
    else
    {
        int x;
        x = queue[front];
        printf("\n\t\tThe front element is %d",x);
        printline();
    }
}

void display()
{
    int i;
    if (front == -1 && rear == -1)
    {
        printf("\n\t\tUnderflow condition\n");
        printline();
    }
    else if(front > N-1 || front == rear)
    {
        printf("\n\t\tAll the elements are dequeued. No elements to display\n");
        printline();
    }
    else
    {
        printf("\n\tThe elements in the queue are:\t");
        for (i = front; i < rear; i++)
        {
            printf("%d \t", queue[i]);
        }
        printline();
    }
}

void printline()
{
    printf("\n------------------------------------------------------------------------------------------\n");
}