GATE CSE 2005 | Question: 1, ISRO2017-55

Question

What does the following C-statement declare?

int (*f) (int * );

• A. A function that takes an integer pointer as argument and returns an integer

• B. A function that takes an integer as argument and returns an integer pointer

• C. A pointer to a function that takes an integer pointer as argument and returns an integer

• D. A function that takes an integer pointer as argument and returns a function pointer

Comments

https://www.youtube.com/watch?v=LPABbqfElA8&list=PLsFENPUZBqipuTJXgm7xAOR0UnY_8OY07&index=31

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B,D are incorrect as they are not returning INT

A is incorrect because it is not a function,

LOL, it is a function pointer

hence C

Answer 1

• A. A function that takes an integer pointer as argument and returns an integer $\Rightarrow int \ f (int *)$

• B. A function that takes an integer as argument and returns an integer pointer $\Rightarrow int * f (int )$

• C. A pointer to a function that takes an integer pointer as argument and returns an integer $\Rightarrow$

  int (*f) (int * );

So, answer is C.

Comments

A function that takes an integer pointer as argument and returns a pointer to a function that takes no arguments and returns integer.

f(int*)

A function that takes an integer pointer as argument and returns a pointer to a function that takes no arguments and returns integer.

int (*f(int*))()                        

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Thanks @Ashish Subscription for the wonderful "Brahmastra"

More on function pointers : Lecture 08 - Function Pointers (cmu.edu)

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thanks @Abhrajyoti00 , good read on function pointers. 

Answer 2

Answer is option C... This is the proptotype to declare a pointer to a function

Answer 3

http://www.geeksforgeeks.org/complicated-declarations-in-c/

Good information to go through

Answer C

Answer 4

By clockwise spiral rule, answer is C

A very good read to read function description http://c-faq.com/decl/spiral.anderson.html

Answer 5

The answer is C.

Detailed video explanation: https://youtu.be/0an69DcHsT0?si=-dG4A4nFKY895hx_

Comments

Indeed Useful , thanks

Answer 6

Small Trick For How to Read 

• Start at the variable name.

• Go right (but respect parentheses).

• If you can’t go right, go left.

• Keep spiraling out until you’ve read the whole declaration.