C Program for Circular Queue Using Array with Queue Data Structure

 

C Program for Circular Queue Using Array with Queue Data Structure

#include<stdio.h>

#include<stdlib.h>

#define MAX 10

//declaration of Circular Queue Array Structure

typedef struct CircularQueueArray{

int arr[MAX];

int rear,front;

}CQueue;

//function declarations

void insert(CQueue*);

void delete(CQueue*);

void display(CQueue*);

void initialize(CQueue*);

//starting of the main function

int main(){

CQueue* q = (CQueue*)malloc(sizeof(CQueue)); //creating a pointer variable of the circular Queue structure

int a;

do{

printf("\n What do you want  to do with the Queue?\n");

printf("\n 0:Initialize \n 1:Insert \n 2:Delete \n 3:Display \n 4:Exit \n");

scanf("%d",&a);

switch(a){

case 0: initialize(q);break;

case 1: insert(q);break;

case 2: delete(q);break;

case 3: display(q);break;

            case 4: exit(0);

default: printf("Wrong Input!Try again:\n");

}

}while(1); //infinite loop for menu

return 0;

}

//Initialize function for eliminating the garbage values from the queue array

void initialize(CQueue* q){

int i;

for(i=0;i<MAX;i++){

q->arr[i]=0;

}

q->rear=q->front=-1;

}

//Insert [through rear] integer data into queue

void insert(CQueue* q){

if((q->front==0&&q->rear==MAX-1)||(q->rear==q->front-1)){

printf("Queue is overflowed,can't insert.");

}

else{

if(q->front==-1&&q->rear==-1)

q->front=q->rear=0;

else if(q->rear==MAX-1&&q->front>0)

q->rear=0; //rear moves circular way

else

q->rear++;

printf("Enter data:\n");

scanf("%d",&q->arr[q->rear]);

}

}

//Delete [through front] data from queue

void delete(CQueue* q){

if(q->front==-1){

printf("Queue underflow,nothing to delete.");

}

else{

printf("Deleted:%d",q->arr[q->front]);

if(q->front==MAX-1)

    q->front=0; //front moves circular way

else if(q->front==q->rear)

q->front=q->rear=-1;

else

    q->front++;

}

}

//Display the values of the queue

void display(CQueue* q){

if(q->front==-1)

printf("Queue is empty,no items to be displayed.");

else{

int i;

printf("Queue elements are:\n");

if(q->front<=q->rear){

for(i=q->front;i<=q->rear;i++){

printf("%d\t",q->arr[i]);

}

}

else{

for(i=0;i<=q->rear;i++){

printf("%d\t",q->arr[i]);

for(i=q->front;i<MAX;i++){

printf("%d\t",q->arr[i]);

}

}

}

}

}

Output:-

 What do you want to do with the Queue?

 0:Initialize 

 1:Insert 

 2:Delete 

 3:Display 

 4:Exit 

0

 What do you want to do with the Queue?

 0:Initialize 

 1:Insert 

 2:Delete 

 3:Display 

 4:Exit 

1

Enter data:

1

 What do you want to do with the Queue?

 0:Initialize 

 1:Insert 

 2:Delete 

 3:Display 

 4:Exit 

1

Enter data:

2

 What do you want to do with the Queue?

 0:Initialize 

 1:Insert 

 2:Delete 

 3:Display 

 4:Exit 

1

Enter data:

3

 What do you want to do with the Queue?

 0:Initialize 

 1:Insert 

 2:Delete 

 3:Display 

 4:Exit 

1

Enter data:

4

 What do you want to do with the Queue?

 0:Initialize 

 1:Insert 

 2:Delete 

 3:Display 

 4:Exit 

1

Enter data:

5

 What do you want to do with the Queue?

 0:Initialize 

 1:Insert 

 2:Delete 

 3:Display 

 4:Exit 

1

Queue is overflowed, can't insert.

 What do you want to do with the Queue?

 0:Initialize 

 1:Insert 

 2:Delete 

 3:Display 

 4:Exit 

3

Queue elements are:

1       2       3       4       5

 What do you want to do with the Queue?

 0:Initialize 

 1:Insert 

 2:Delete 

 3:Display 

 4:Exit 

2

Deleted:1

 What do you want to do with the Queue?

 0:Initialize 

 1:Insert 

 2:Delete 

 3:Display 

 4:Exit 

2

Deleted:2

 What do you want to do with the Queue?

 0:Initialize 

 1:Insert 

 2:Delete 

 3:Display 

 4:Exit 

4

Try here:-

https://onlinegdb.com/XoGEqMCSW