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    <p>Memory for new nodes has to come from <em>somwhere</em>. You can certainly create individual variables and link them manually:</p> <pre><code>link a, b, c; ... a.next = &amp;b; b.next = &amp;c; c.next = NULL; </code></pre> <p>As you can imagine, this approach doesn't scale; if you want more than 3 elements in your list, you'd have to allocate more than 3 <code>link</code> variables. Note that the following <em>won't</em> work:</p> <pre><code>void addToList( link *b ) { link new; ... b-&gt;next = &amp;new; } </code></pre> <p>because <code>new</code> <em>ceases to exist</em> when the <code>addToList</code> exits, so that pointer is no longer meaningful<sup>1</sup>.</p> <p>What you <em>can</em> do is use an array of <code>link</code> as your "heap", and allocate from that array. You'll need to keep track of which elements are available for use; an easy way of doing that is initializing the array so that each <code>a[i]</code> points to <code>a[i+1]</code> (except for the last element, which points to NULL), then have a pointer which points to the first available element. Something like the following:</p> <pre><code>// You really want your "heap" to have static storage duration static link a[HEAP_SIZE]; // Initialize the "heap" for ( size_t i = 0; i &lt; SIZE - 1; i++ ) a[i].next = &amp;a[i+1]; a[i].next = NULL; // Set up the freeList pointer; points to the first available element in a link *freeList = &amp;a[0]; // Get an element from the "heap" link *newNode = freeList; freeList = freeList-&gt;next; newNode-&gt;next = NULL; // Add a node back to the "heap" when you're done with it: deletedNode-&gt;next = freeList; freeList = deletedNode; </code></pre> <p>Again, you're limited in how many list nodes you can create, but this way you can create a large enough "heap" to satisfy your requirements. </p> <p><hr> <sup>1. Obviously, the phsyical memory location that <code>new</code> occupied still exists, but it's now free for other processes/threads to use, so the value contained in that address will no longer be what you expect.</sup></p>
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    1. POc - creating a linked list without malloc
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    1. USJohn Bode
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    1. COokay.i edited my question with my new code solution with malloc.could you possibly point out my error,as i cant seem to find it?(it only includes insert and remove so far)
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    2. COFor the `Add` and `Remove` functions, you need to pass `a` as a *pointer* to `List`. Remember that C passes all function parameters *by value*, so the formal parameter is a different object in memory from the actual parameter; any changes made to the formal parameter won't be reflected in the caller.
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    3. COokay.also,how does the list in c# function without any mallocing?(for example:http://pastebin.com/9VU5BAx5 notice the insert) also,i solved the code's problem without passing a as a pointer to the list,but as the actual list
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