C++ name clashes and multiple inheritance: will this program compile, and what does the qualified call print? #include<iostream.h> static int Result; class India{ public: void Change(int x=10,int y=20,int z=30){ cout << x+y+z; } void Display(int x=40, float y=50.00){ Result = x % x; cout << Result; } }; class CuriousTab{ int x,y; public: void Change(int x,int y=50){ cout << x+y; } }; class CuriousTab: public India, public CuriousTab{ public: void Display(int x=10,int xx=100,int xxx=1000){ Result = x + xx % x * x; cout << Result; } }; int main(){ CuriousTab objCuriousTab; objCuriousTab.India::Display(10, 20.00); }
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AThe program will print the output 0.
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BThe program will print the output 10.
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CThe program will print the output 30.
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DThe program will print the output 40.
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EThe program will report compile time error.
Answer
Correct Answer: The program will report compile time error.
Explanation
Introduction / Context:This contrived code intentionally collides names: there are two different classes both named CuriousTab, and the latter tries to inherit from itself and from the earlier class of the same name, which is illegal. The snippet probes understanding of class redefinition and inheritance rules.
Given Data / Assumptions:
- One class named
CuriousTabis defined, then another class with the same identifier is declared again. - The second definition attempts
class CuriousTab: public India, public CuriousTab. - Old
iostream.hheaders are used but do not affect this error.
Concept / Approach:In C++, a class name cannot be redeclared with a different definition in the same scope. Moreover, a class cannot directly inherit from itself; attempting to do so results in a compilation error.
Step-by-Step Solution:1) The second class CuriousTab conflicts with the first—ODR/definition violation.2) The base-list public CuriousTab tries to use the very class being defined (self-inheritance), which is ill-formed.3) The compiler will issue errors before any runtime behavior can occur.
Verification / Alternative check:Rename one of the classes or place them in different namespaces; the program will then compile, and qualified calls will be resolvable.
Why Other Options Are Wrong:They assume successful compilation and runtime output, which is impossible here due to fundamental declaration errors.
Common Pitfalls:Assuming C++ allows redefinition or shadowing of class names in the same scope; it does not.
Final Answer:The program will report compile time error.