MCQs on Pointer in C

A pointer is a special variable in C/C++ that holds the memory address of another variable rather than its direct value.

The ampersand (&) is the address-of operator, used to retrieve the memory location of a variable.

The asterisk (*) is the dereferencing operator, used to access the value stored at the memory address held by a pointer.

While pointers can point to any type, internally, a memory address is treated as a numerical value, typically represented as an integer (specifically an unsigned int).

Casting is used to convert a pointer of one type to another (e.g., void* to int*). Mathematical operations like division and multiplication are not permitted on pointers.

sizeof(*p) is the size of a char (1 byte), and sizeof(p) is the size of a pointer, which is 2 bytes in a 16-bit environment like Turbo C.

A pointer provides a way to access and manipulate data by referencing its specific location in memory.

The asterisk (*) acts as the 'value at' operator, allowing the programmer to get the content of the address the pointer is pointing to.

In C/C++, the asterisk (*) prefix is used during variable declaration to indicate that the variable is a pointer.

The standard syntax for declaring an integer pointer is 'datatype *variablename;'.

Functions in C can return pointers to variables, though care must be taken not to return pointers to local variables that go out of scope.

The 'this' pointer is an implicit parameter to all non-static member functions, pointing to the object for which the function is called.

The code declares an integer p with value 1, points ptr to p, and then dereferences ptr to print the value 1.

Incrementing *ptr changes the value of p. Since *ptr and p refer to the same memory location, both evaluate to 6.

While pointers usually increase speed and efficiency, the provided answer key indicates they 'decrease execution speed,' likely referring to the overhead of indirection in certain specific contexts.