Priority Queue C + + implementation and application

#include <iostream>
#include <stdlib.h>
using namespace Std;
Number of priority queue array elements
const int maxpqsize = 50;
Template<class t>
Class pqueue{
Private
int count;
T Pqlist[maxpqsize];
Public
Pqueue (void);
void Pqinsert (const t& Item);
T pqdelete (void);
void Clearpq (void);
Detection Priority Queue Status action
int pqempty (void) const;
int pqfull (void) const;
int pqlength (void) const;

};


Template <class t>
Pqueue<t>::P queue () {
Count = 0;
}
Template<class t>
int pqueue<t>::P qempty () const{
return count==0;
}
Template<class t>
void Pqueue<t>::P qinsert (const t& Item) {

if (count = = maxpqsize) {
cerr<< "The queue has overflowed!" <<endl;

}
Place elements at the end of the queue and make count+1
Pqlist[count] = Item;
count++;
}
Place the tail element at the maximum priority element count--
Template<class t>
T pqueue<t>::P Qdelete () {
T min;
int i,minindex = 0;
if (Count > 0) {
Find the lowest value in the Pqlist the very subscript
Min = pqlist[0];//assumes that the first element is the minimum value
Sequential access elements Modify the minimum and subscript values
for (i = 1; i < count; i++)
if (Pqlist[i] < min) {
min = Pqlist[i];
Minindex = i;
}

Move the tail element into the smallest element and subtract count by one
Pqlist[minindex] = pqlist[count-1];
count--;
}else{
cerr<< "Deleting from an empty Pqueue" <<endl;
}
Return min;//returns the minimum value
}

Application

#include <iostream>
#include <iomanip>
#include <fstream>
#include "PQueue.h"
/* Run this program using the console Pauser or add your own getch, System ("pause") or input loop */
Define a record for a request order
Enum Staff{manager,supervisor,worker
};//Employee type Manager highest priority
struct Jobrequest
{
Staff Staffperson;
int Jobid;
int jobtime;
};//Working Status
int operator< (const jobrequest& a,const jobrequest& b) {
return A.staffperson < B.staffperson;
}

void Printjobinfo (Jobrequest PR) {
Switch (Pr.staffperson) {
Case Manager:
cout << "Manager";
Break
Case Supervisor:
cout<< "Supervisor";
Break
Case Worker:
cout<< "Worker";
Break
}
Cout<<pr.jobid << "" <<PR.jobTime<<endl;
}

void printjobsummary (int jobservicesuse[]) {
cout<< "\ntotal support usage\n";
cout<< "Maager" &LT;&LT;SETW (3)
&LT;&LT;JOBSERVICESUSE[0]&LT;&LT;SETW (3) <<endl;
cout<< "Supervisor" &LT;&LT;SETW (3) <<jobServicesUse[1]<<endl;
cout<< "Worker" &LT;&LT;SETW (3) <<jobServicesUse[2]<<endl;
}
int main (int argc, char** argv) {
Process no more than 50 service request orders
Pqueue<jobrequest> Jobpool;
Read the service request form from fin
Ifstream fin;
Hours of service for each type of employee
int jobservicesuse[3]={0,0,0};
Jobrequest PR;
Char ch;
Open the input file Job.dat quit the program if it fails
Fin.open ("Job.dat", ios::in);
if (!fin) {
cerr<< "Cannot open file Job.dat" <<endl;
}

Read each request from a file and insert it into the priority queue Jobpool
Each line starts with a character that indicates the employee category
while (Fin>>ch) {
Switch (CH) {
Case ' M ': Pr.staffperson = Manager;
Break
Case ' S ': Pr.staffperson = Supervisor;
Break
Case ' W ': Pr.staffperson = Worker;
Break
Default:break;
}
Read Jobid and Jobtime in PR
fin>>pr.jobid;
fin>>pr.jobtime;
To insert a PR into the priority queue
cout<<pr.jobid<< "* * *" <<endl;
Jobpool. Pqinsert (PR);
}

Remove the service from the priority queue and output information about the service
cout<< "Category Job ID job Time" <<endl;
while (!jobpool. Pqempty ()) {
PR = Jobpool. Pqdelete ();
Printjobinfo (PR);
Cumulative service time for each type of employee
Jobservicesuse[int (Pr.staffperson)]+=pr.jobtime;
}
Printjobsummary (Jobservicesuse);
return 0;
}

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Priority Queue C + + implementation and application