Page 194 - DCAP201_FUNDAMENTALS_OF_DATA_STRUCTURES

Unit 11: Operations and Applications of Queues

11. The allocation of memory for a particular resources are maintained in queue. Notes
12. An operating system does not makes use of a queue for scheduling processes or jobs.
13. Queue is used when data is transferred synchronously between two processes.
14. When a resource like CPU is shared between among multiple consumers, a queue solves
the hatchet.
15. All the input output calls made by the disk to and from the memory are handled by a stack.

Case Study C Program to Enqueue and Dequeue in a
Circular Queue using Singly Linked List

#include<stdio.h>
#include<conio.h>
#include<alloc.h>
typedef struct nodes
{
int x;
struct nodes *next;
}node;
//Function Declarations
void enqueue(node **,node **, int);//Use call by reference node **
is pointer to pointer
int dequeue(node **,node **);
void display(node *);
void main()
{
node *front=NULL, *rear=NULL;
int choice,element;
clrscr();
do
{
printf("\n1. Enqueue\n2. Dequeue\n3.Print Linked
List\n4.Exit\nChoice : ");
scanf("%d",&choice);
switch(choice)
{
case 1:
printf("Enter the element to insert : ");
scanf("%d",&element);

Contd...

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