Question

I have a project with priority queues and reqular queues.
I need to organize products by IDs from min to max using priority queues.

And then using reqular queues I need to put them into 3 categories:
(over-stock, under-stock, within limits); so the output should look like this:

UnderStock

14887 $10 14

15678 $1 298

OverStock

12565 $4 539

18967 $12 401

StockWithinLimits

19847 $2 220

I wrote this code, but something is off that I am not sure and my out put looks like:

OverStock

12565 $4 539

UnderStock

14887 $10 14

UnderStock

15678 $1 298

OverStock

18967 $12 401

StockWithInLimits

19847 $2 220

int main() 
{ 
    ifstream inFile; // file containing operations 
    ofstream outFile; // file containing output 
    string inFileName = "product.txt"; 
    string outFileName = "result.txt"; 
    inFile.open (inFileName.c_str()); 
    outFile.open (outFileName.c_str()); 
    ItemType item;//declare a temp item that trows into pQue 
    PQType<ItemType> pqueue(50);//priority queue that sorts items by ID 
    QueueADT <ItemType> que; 
    QueueADT <ItemType> lowQ;
    QueueADT <ItemType> highQ;
    QueueADT <ItemType> withinQ;

    while ( item.readProduct (inFile) ) 
    { 
        pqueue.Enqueue(item); 

    } 

    while (!pqueue.IsEmpty()) 
    { 
        pqueue.Dequeue (item); 
        int tempcurinvent = item.getcurrentInventory (); 
        int tempmax = item.getMax (); 
        int tempmin =item.getMin (); 

    if ((tempcurinvent < tempmin) && (tempcurinvent < tempmax))//UnderStock 
        {
            lowQ.Enqueue (item);
        }

if ((tempcurinvent < tempmax) && ( tempcurinvent  > tempmin)) //WithINLimits
        { 
            withinQ.Enqueue (item);
        } 
else if ((tempcurinvent > tempmin) && (tempcurinvent > tempmax))//OverStock 
        { 
            highQ.Enqueue (item);
        }
        outFile << "UnderStock" << endl;
        item.printProduct (outFile);
        lowQ.Dequeue (item);

        outFile << "WithINLimits:" << endl;
        item.printProduct (outFile); 
        withinQ.Dequeue (item);

        outFile << "OverStock" << endl; 
        item.printProduct (outFile); 
        highQ.Dequeue (item);

    }

    inFile.close (); 
    outFile.close (); 



  return 0; 
} 

Answer 1

An odd use for a priority queue but I suppose that is the requirements.

(1) You put everything in the pqueue. That’s good. You should then empty the pqueue and using the under/over/within logic put the items into one of the three regular queues. THEN read each of queues (printing the header “over”, “under”, “within” first) and print them out.

(2)

QueueADT <int> que;

que.Enqueue (n);

looks wrong. Why are you queing an int and not the item? Why do you have one queue and not three? This applies to que.Deque(n) statements as well.

(3) You don’t really need compound IF statements. Presumably if something is below the minimum it is also below the maximum.

So something like

 if belowMin
     put in lowQ
     readagain

 if aboveMax
     put in highQ
     readagain

 put in withinQ

Also be careful to make sure you want item < max rather than item <= max, depending on what the specs say.

EDIT

These neeed to be outside the current while loop:

outFile << "UnderStock" << endl;
while (!lowQ.IsEmpty())
{
    lowQ.Dequeue (item);
    item.printProduct (outFile);
}

outFile << "WithINLimits:" << endl;
while (!withinQ.IsEmpty())
{
    withinQ.Dequeue (item);
    item.printProduct (outFile);
}

outFile << "Overstock:" << endl;
while (!highQ.IsEmpty())
{
    highQ.Dequeue (item);
    item.printProduct (outFile);
}