Issue
I got a Question in a mock test which is not running in IDE but I could not understand the concept behind that piece of code given in test.
printf (“%c, %c”, *( (char*) q + 1) , *( (char*) q + 2) ) ;
Here how an pointer to struct q can access the members of pointers using numbers.
Here is the link for the code
https://ide.geeksforgeeks.org/7V6mVJZvre
Solution
In c, struct members just memory space mapped to that struct definition. A struct with three chars means 3 byte space mapped to the this struct.
q is a pointer. So q + 1
means one address forward to the base struct address
(char*)
means this is not a struct anymore this is a char pointer
*( (char*) q + 2) )
or simply *x means dereference the pointer so get the char value.
There are some exceptions (if not all members are the same type) check Structure padding and packing
Answered By - Furkan Answer Checked By - Candace Johnson (PHPFixing Volunteer)
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