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    <p>you have an error in the add of a new element in the middle or in the end of the linked list. in your <code>addStoredItem</code> function you make a pointer from your newItem to the currentItem but you do not take account to have a link from previous element to the newItem</p> <p>initial linked list befor calling <code>addStoredItem</code></p> <pre><code>item1--&gt;item2--&gt;item4--&gt;item5 </code></pre> <p>Linked list afetr calling <code>addStoredItem</code> in order to add <strong>item3</strong></p> <pre><code>item1--&gt;item2--&gt;item4--&gt;item5 ^ | item3 </code></pre> <p>so as you can see you have added the new item at the head of the sub linked list starting from <strong>item4</strong> but you do not make link from <strong>item2</strong> to <strong>item3</strong> so that we have to keep a pointer to the previous item in order to complete the link.</p> <p>the <code>add_item()</code> function allow to add item in the head</p> <p>The same thing if you try to add item at the end of the linked list</p> <pre><code>item1--&gt;item2--&gt;item4--&gt;item5 NULL ^ | item6 </code></pre> <p>the <strong>item6</strong> has added as separate head and there is no link from <strong>item5</strong> (previous) to item6 (new)</p> <p>so your <code>addStoredItem()</code> function could be fixed like this</p> <pre><code>ListItem* addSortedItem(ListItem *p_head, char *s){ if(p_head==NULL)//if the list is empty, we add to the beginning return add_item(p_head,s); struct ListItem* p_new_item = malloc(sizeof(ListItem)); ListItem *p_current_item = p_head; //makes a pointer to the head of the list ListItem *p_prev_item = NULL; //FIXED while (p_current_item) { // Loop while the current pointer is not NULL printf("entering while loop with current=%s\n",p_current_item-&gt;s); // now we want to look at the value contained and compare it to the value input if(aThenB(s,p_current_item-&gt;s)!=TRUE){ // if A goes after B, we want to go on to look at the next element p_prev_item = p_current_item; //FIXED p_current_item=p_current_item-&gt;p_next; } else if (aThenB(s,p_current_item-&gt;s)==TRUE) {printf("entered elseif\n"); break; } else {printf("WHY DID WE EVER REACH THE ELSE!?"); return p_head;} } if (p_prev_item!=NULL) //FIXED p_prev_item-&gt;p_next=add_item(p_current_item,s); //FIXED else //FIXED p_head=add_item(p_current_item,s);//FIXED return p_head; //FIXED } </code></pre> <p>the fixed lines are indicated with <code>//FIXED</code></p>
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    1. POAdd to Linked List in sorted order, having trouble with pointers
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    1. POAdd to Linked List in sorted order, having trouble with pointers
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    1. COCan you explain the line `p_prev_item->p_next=add_item(p_current_item,s);`? I've tried implementing this (blindly) and it works but i'm a bit confused what is actually happening. Here's what my understanding of pointers says: the first arrow means that we are dealing with a pointer to the pointer contained in the p_prev_item struct; which i believe is a similar idea to a double pointer (**p). before that line, `p_prev->p_next = current_item` (by definition); so why can't we just change what current_item is by saying `p_current_item=add_item(p_current_item,s);`
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    2. COanswer updated for more explanation
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    3. COThanks! :-) there's still an issue with it- it's still unable to put things in the middle properly. But I'm going to give it a go to work myself on that issue first :-)
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