Answer the questions (i) to (iv) based on the following: class Ground int Rooms; protected: void Put(); public

Question of 97

Q. Answer the questions

(i) to

(iv) based on the following: class Ground { int Rooms; protected: void Put(); public: void Get(); }; class Middle : private Ground { int Labs; public: void Take(); void Give(); }; class Top : public Middle { int Roof; public: void In(); void Out(); }; void main() { Top T; }

(i) Which type of Inheritance out of the following is illustrated in the above example? Single Level Inheritance, Multilevel Inheritance, Multiple Inheritance

(ii) Write the names of all the members, which are directly accessible by the member function Give() of class Middle.

(iii) Write the names of all the members, which are directly accessible by the member function Out() of class Top.

(iv) Write the names of all the members, which are directly accessible by the object T of class Top declared in the main() function.

(OR)

Consider the following class HeadQuarter class HeadQuarter { int Code; char Des[20]; protected : char Address[40]; public: void Get(){cin>>Code;gets(Des);gets(Address);} void Put(){cout<<Code<<Des<<Address<<endl;} }; Write a code in C++ to protectedly derive another class FrontOffice from the base class HeadQuarter with following members. Data Members Location of type character of size 10 Budget of type double Member Functions A constructor function to assign Budget as 100000 Assign() to allow user to enter Location and Budget Display() to display Location and Budget

CBSECBSE Class XII Board 2019Subjective· 4mImportance★★★★★est

0% · 0/97 Questions

🔒 Locked · start free trial →

You're viewing a preview — the full solution, concept, methods & PYQ mapping are locked.

Start your 14-day free trial to unlock the full solution →

Part (a)Concept understanding — Function Call Handling

Function Call Handling

Think about what happens when you ask a friend for a favour. You stop what you're doing, explain what you need, and then wait while your friend does the work. Once they finish, they come back to you with the result, and you resume whatever you were doing. That simple back-and-forth is the essence of how function calls work in programming.

The Everyday Intuition

Imagine you're cooking a meal. You have a recipe book open. The main recipe says "prepare the sauce" — but it doesn't list every single step for making the sauce right there. Instead, it expects you to know a separate sauce recipe. So you pause the main cooking, go make the sauce, and when it's ready, you return to the main dish and continue. The sauce recipe is like a function: a self-contained set of instructions that does one specific job.

In programming, a function call is exactly this: the main program says "go do this specific task," hands over any necessary information, waits for the task to complete, and then gets back whatever result the function produced.

The Precise Meaning

A function call is the instruction that tells the computer to execute a predefined block of code — the function — and then return control back to the point where the call was made. The function itself is a named, reusable set of instructions that performs a particular operation.

When a function is called, three things happen in sequence:

The current task is paused — the computer remembers exactly where it was in the main program.
Control is transferred to the function, along with any data the function needs to do its job (these are called arguments or parameters).
The function runs its instructions, produces a result (if any), and returns control — along with that result — back to the exact spot where the call was made.

Note

The key idea is temporary suspension. The main program does not end when a function is called; it simply steps aside, lets the function do its work, and then picks up exactly where it left off. This is different from jumping to a completely new program or starting over.

Why It Matters

Function call handling is not a trivial detail — it is the backbone of how programs are organised. Without it, every program would be one long, flat list of instructions, impossible to manage beyond a few dozen lines.

Here is why this concept is so important:

Reusability — You write a function once and call it as many times as needed. The same "calculate tax" function can be called for every customer without rewriting the logic.
Modularity — A program is broken into small, independent pieces. Each function does one thing well. This makes the program easier to understand, test, and fix.
Abstraction — When you call a function, you do not need to know how it works internally. You only need to know what it does and what information to give it. This is like driving a car without understanding the engine.
Readability — A program that uses function calls reads almost like an outline: "process order, calculate discount, send confirmation." Each step is a function name that describes what happens.

Important

The most common mistake beginners make is thinking that a function call "inserts" the function's code into the main program. It does not. The function's code stays in its own place. The call merely transfers control temporarily. This distinction matters because it explains how the same function can be called from many different places without duplicating code.

How the Computer Keeps Track …

Part (b)Concept understanding — Function Call Handling

Function Call Handling

The Everyday Intuition

The Precise Meaning

When a function is called, three things happen in sequence:

The current task is paused — the computer remembers exactly where it was in the main program.
Control is transferred to the function, along with any data the function needs to do its job (these are called arguments or parameters).
The function runs its instructions, produces a result (if any), and returns control — along with that result — back to the exact spot where the call was made.

Note

Why It Matters

Here is why this concept is so important:

Reusability — You write a function once and call it as many times as needed. The same "calculate tax" function can be called for every customer without rewriting the logic.
Modularity — A program is broken into small, independent pieces. Each function does one thing well. This makes the program easier to understand, test, and fix.
Abstraction — When you call a function, you do not need to know how it works internally. You only need to know what it does and what information to give it. This is like driving a car without understanding the engine.
Readability — A program that uses function calls reads almost like an outline: "process order, calculate discount, send confirmation." Each step is a function name that describes what happens.

Important

How the Computer Keeps Track …

Start your 14-day free trial to unlock the full solution →

Part (a): the example is multilevel inheritance; visibility of members through the chain depends on the access specifiers, giving the accessible-member lists below. Part (b): a protectedly-derived FrontOffice class with the required data members, a constructor, Assign() and Display().

Part (a)

The chain is Ground → Middle (private derivation) → Top (public derivation).

(i) Type of inheritance: one class derived from another which is derived from a third → Multilevel Inheritance.

(ii) Members directly accessible inside Give() of Middle:

Middle's own members: Labs, Take(), Give().
Inherited from Ground (private derivation): Ground's public Get() and protected Put() become private members of Middle, so they are accessible within Middle's own methods.
Ground's private Rooms is never accessible. → Labs, Take(), Give(), Get(), Put().

(iii) Members directly accessible inside Out() of Top:

Top's own members: Roof, In(), Out().
Inherited from Middle (public derivation): Middle's public Take(), Give() remain accessible; Middle's private Labs is not.
Get()/Put() had become private in Middle, so they are not inherited-accessible in Top. → Roof, In(), Out(), Take(), Give().

(iv) Members accessible to object T of Top in main():

An object can use only public members. Top's public members are In(), Out(); through public derivation Middle's public Take(), Give() are also public in Top. Everything from Ground is private in Middle, hence unavailable. …

Start your 14-day free trial to unlock the full solution →

←Previous chapterCh 6Searching

Q.Answer the questions

Part (a)

🎓Unlock everything free for 14 days

Unlock everything free for 14 days