printing a queue

This is a discussion on printing a queue within the C Programming forums, part of the General Programming Boards category; i seem to be having a problem printing a queue. when i dequeue, i am returning the value that was ...

  1. #1
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    printing a queue

    i seem to be having a problem printing a queue. when i dequeue, i am returning the value that was dequeued, and letting the user know when the queue is empty, but when i go to print the queue, the values entered are still there. i think it has to do with my dequeue function. here's the code

    Code:
    //in main if choice = 6 then print the queue
            if(choice == 6)
            {
                print_queue(q);
            }
    
    //remove the front value
    int dequeue(struct queue* q)
    {
        int val = q->store[q->front];
        q->front = (q->front + 1) % q->size;
    
        return val;
    }
    
    //print queue function
    void print_queue(struct queue* q)
    {
        int j;
        
        for(j=0; j < q->back; j++)
            printf("%d ", q->store[j]);
            printf("\n");
    }

  2. #2
    and the Hat of Guessing tabstop's Avatar
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    Code:
    for(j=q->front; j < q->back; j++)
    Edit: Also, I don't know if you're doing "rollaround" (where q->front might be 15 and q->back might be 2, so that the queue goes 15, 16, 17, 18, 19, 0, 1, 2), but if so, then you should check != rather than <.

  3. #3
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    ok thanks that really helped!

  4. #4
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    How are you getting yours to print that way? When I changed my loop like that all it printed for me was a new line...

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