Thread: Linked List Queue

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    Linked List Queue

    for my assignment, i had to simulate a taxi rank that is implemented as a queue via an array that can hold up to a maximum of six taxis., which i completed but now its telling me to implement it in a linked list queue, im not sure how to start this. any help will be welcome.

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    Start here Linked Lists in C Tutorial - Cprogramming.com

    The logic isn't any different. It's still FIFO. It still uses pointers to front and rear. Now you implement with dynamic nodes of data and have to solve maintaining the maximum queue size differently.

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    SAMARAS std10093's Avatar
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    Quote Originally Posted by Tclausex View Post
    Another source for someone to really understand linked lists can be found here.
    Code - functions and small libraries I use


    It’s 2014 and I still use printf() for debugging.


    "Programs must be written for people to read, and only incidentally for machines to execute. " —Harold Abelson

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    C++ Witch laserlight's Avatar
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    Quote Originally Posted by std10093 View Post
    Another source for someone to really understand linked lists can be found here.
    Can't say I like that unnecessary pointer typedef.
    Quote Originally Posted by Bjarne Stroustrup (2000-10-14)
    I get maybe two dozen requests for help with some sort of programming or design problem every day. Most have more sense than to send me hundreds of lines of code. If they do, I ask them to find the smallest example that exhibits the problem and send me that. Mostly, they then find the error themselves. "Finding the smallest program that demonstrates the error" is a powerful debugging tool.
    Look up a C++ Reference and learn How To Ask Questions The Smart Way

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    SAMARAS std10093's Avatar
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    I see what you saying. Salem had also pointed out a bad effect of typedef in similar situations, but as I have written in the link "This code comes from the course of ip, from DIT, Athens.", so I feel a bit uncomfortable to modify it.
    Code - functions and small libraries I use


    It’s 2014 and I still use printf() for debugging.


    "Programs must be written for people to read, and only incidentally for machines to execute. " —Harold Abelson

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    young grasshopper jwroblewski44's Avatar
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    Quote Originally Posted by std10093 View Post
    Another source for someone to really understand linked lists can be found here.
    to really understand?

    The code may be all and good. But for someone looking to have the concept explained to them with more than lines of source (confusing at that) code, not a great resource.

    Linked List Basics

    The link provides a pdf document that covers linked lists to exhaustion, along with some sample problems.
    Last edited by jwroblewski44; 03-28-2013 at 03:20 PM.

  7. #7
    SAMARAS std10093's Avatar
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    Do you really read it? It has very good comments in my mind. Reading good and commented code is always helpful. I did not say that the link is the only source of course. But theory only is not enough. This was what made me understand them when on ip and that's why I forward it to others.-
    Code - functions and small libraries I use


    It’s 2014 and I still use printf() for debugging.


    "Programs must be written for people to read, and only incidentally for machines to execute. " —Harold Abelson

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    young grasshopper jwroblewski44's Avatar
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    >Do you really read it?
    Well, I tried. But the formatting is 'not great'. And to have a comment on every single line is not what you want. In fact, it takes away from the code by distracting the reader.

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    Master Apprentice phantomotap's Avatar
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    It has very good comments in my mind. Reading good and commented code is always helpful.
    I agree completely.

    That said, the interface itself is pretty decent from what I saw, and I perfectly well understand the comments documenting the intended state of the list. Those comments are great for this, but the sort of thing here is not what we want newbies emulating.

    Code:
    if (n_th(alist, 2, &v))                     /* Return 2nd element */
    That sort of thing is awful. If `n_th' is documented properly, the comment is redundant in the worst way. If someone comes along and changes that to get the third element without updating the comment we have "out of sync" documentation. It is annoying to work with in small doses; in complex projects it can be a significant problem.

    Again, I know this tutorial, but we don't want newbies learning that kind of commenting.

    Soma

  10. #10
    young grasshopper jwroblewski44's Avatar
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    Indeed. I did not mean to say that the code was not an accurate representation of a linked list. Just not "noob-friendly".

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