Pointer declaration - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a pointer in C?

A pointer is a variable that stores the memory address of another variable.

beginner

How do you declare a pointer to an integer in C?

Use the syntax: int *ptr; where ptr is a pointer to an integer.

beginner

What does the asterisk (*) mean in a pointer declaration?

The asterisk (*) indicates that the variable is a pointer to the type specified before it.

intermediate

Explain the difference between int *ptr; and int* ptr;.

Both declare a pointer to an int. The placement of * does not change the meaning; it's a style choice.

intermediate

What happens if you declare a pointer but do not initialize it?

The pointer contains a garbage address and using it without initialization can cause errors or crashes.

Which of the following declares a pointer to a float?

A float *ptr;

B float ptr*;

C *float ptr;

D ptr float*;

The correct syntax is float *ptr; where the asterisk indicates a pointer.

What does the pointer variable store?

A The value of another variable

B The memory address of another variable

C The size of a variable

D The type of a variable

Pointers store the memory address where another variable is located.

How do you declare a pointer to a character?

A ptr char*;

B char ptr*;

C *char ptr;

D char* ptr;

The correct declaration is char* ptr;.

What is wrong with this declaration? int ptr;

A It declares an integer variable, not a pointer

B It declares a pointer to a pointer

C It declares a pointer correctly

D It declares a pointer to a float

Without the asterisk, int ptr; declares a normal integer variable, not a pointer.

Which symbol is used to declare a pointer variable?

A #

B &

C *

D $

The asterisk (*) is used to declare a pointer variable.

Describe how to declare a pointer to an integer and explain what it stores.

Think about how you tell the computer to hold an address instead of a value.

Explain why it is important to initialize a pointer before using it.

Imagine using a map with a wrong address.