SAVITIBAI PHULE UNIVERSITY OF PUNE
S. Y. B.Sc. (Computer Science) Semester III
Practical Examination
SUBJECT: CS-233 Practical course based on CS231
/* Q. 2 Implement a priority queue library (Priority.h) of integers using a static implementation of the queue and implementing the below two operations. Write a driver program that includes queue library and calls different queue operations.
1) Add an element with its priority into the queue.
2) Delete an element from queue according to its priority. */
// File name : "PriorityQ.c"
#include"PriorityQ.h"
int initPQ(struct PriorityQueue *pq)
{
pq->front = pq->rear = -1;
return 0;
}
int isFullPQ(struct PriorityQueue *pq)
{
if(pq->rear == MAX-1)
return 1;
else
return 0;
}
int isEmptyPQ(struct PriorityQueue *pq)
{
if(pq->front == -1)
return 1;
else
return 0;
}
void InsertPQ(struct PriorityQueue *pq, struct data dt)
{
struct data temp;
int i, j;
pq->rear++;
pq->d[pq->rear] = dt;
if(pq->front == -1)
pq->front = 0;
for( i = pq->front; i <= pq->rear; i++)
{
for( j = i+1; j <= pq->rear; j++ )
{
if( pq->d[i].priority > pq->d[j].priority )
{
temp = pq->d[i];
pq->d[i] = pq->d[j];
pq->d[j] = temp;
}
else
{
if( pq->d[i].priority == pq->d[j].priority )
{
if( pq->d[i].order > pq->d[j].order )
{
temp = pq->d[i];
pq->d[i] = pq->d[j];
pq->d[j] = temp;
}
}
}
}
}
}
struct data DeletePQ(struct PriorityQueue *pq)
{
struct data t = pq->d[pq->front];
if( pq->front == pq->rear )
pq->front = pq->rear = -1;
else
pq->front++;
return t;
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// File name : "PriorityQ.h"
#include<stdio.h>
#include<stdlib.h>
#define MAX 10
struct data
{
int item;
int priority;
int order;
};
struct PriorityQueue
{
struct data d[MAX];
int front;
int rear;
};
int initPQ(struct PriorityQueue *pq);
int isFullPQ(struct PriorityQueue *pq);
int isEmptyPQ(struct PriorityQueue *pq);
void InsertPQ(struct PriorityQueue *pq, struct data dt);
struct data DeletePQ(struct PriorityQueue *pq);
//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// File name : "main.c"
#include"PriorityQ.h"
int main(int argc, char *argv[])
{
struct PriorityQueue q;
struct data temp;
int i = 0, ch;
initPQ(&q);
do{
printf("\n1. Insert \n2. Delete \n3. Exit \n");
scanf("%d", &ch);
switch(ch)
{
case 1:
if(isFullPQ(&q))
printf("\n Queue is full.");
else
{
printf("Enter the data and Priority : ");
printf("\nData \t Priority\n");
scanf("%d%d", &(temp.item), &(temp.priority));
temp.order = i++;
InsertPQ(&q, temp);
}
break;
case 2:
if(isEmptyPQ(&q))
printf("\n Queue is Empty");
else
{
temp = DeletePQ(&q);
printf("Data = %d \t Priority = %d \n", temp.item, temp.priority);
}
break;
default:
printf("Thank you visit again ....\n\n");
break;
}
}while(ch>0 && ch<3);
system("PAUSE");
return 0;
}
