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    <p>The book you're looking at, <em>Programming Interviews Exposed</em>, is (as far as I can tell) <em>not</em> a book on C++, but rather a book meant to prepare you to answer the kinds of questions that might be asked at a typical technical interview. I wouldn't take anything in the book as a best C++ practice unless it's labelled as such (and perhaps not even then).</p> <p>The advice to put the next pointer first in a linked list node structure comes from languages like C, where you can't rely on real, compiler-supported inheritance. The idea is, in fact, to implement something like inheritance yourself by piggybacking data onto the linked list node structure. Consider:</p> <pre><code>typedef struct LinkedList { LinkedListNode* next; int type; } typedef struct Person { LinkedList listNode; char name[64]; int age; } typedef struct Address { LinkedList listNode; char streetAddress[128]; char city[32]; char state[2]; char zip[10]; } typedef struct Employee { Person person; int department; int salary; } </code></pre> <p>LinkedList here is a base type -- not good for much by itself, but useful as a starting point for nodes with more data. You don't have to know anything about the other types in order to perform linked list operations on a node... you can cast any node pointer to LinkedList* and access the information you need. So, you can have a list of Person and list of Address, and both can be manipulated with the same set of routines. Likewise, you can cast a Employee* to a Person* and use any operations that you've written for Person on Employee as well. If you assign appropriate constants to LinkedList's <code>type</code> field, you can even mix PersonNode and use the <code>type</code> field to determine the type of each node later.</p> <p>This was a useful way to program 20+ years ago. It still works, of course, but most people would choose to let the compiler manage inheritance for them if they have the option, and all modern object-oriented langauges do offer that option.</p> <p><strong>Lesson:</strong> Understand the technique in case you come across it in old code, but choose a different implementation for your new code if you can.</p>
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    1. COthanks Caleb. Understood the well explained answer and problem.
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      1. USAj Gauravdeep
 

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Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

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