# 2.1: Pointer Review

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Pointers are symbolic representation of addresses. They enable programs to simulate call-by-reference as well as to create and manipulate dynamic data structures. It’s general declaration in C/C++ has the format:

Syntax:

datatype *var_name;

int *ptr;   //ptr can point to an address which holds int data

Here is a visual example of how pointers work: How to use a pointer?

• Define a pointer variable – you must use an asterisk (*) when defining a pointer variable. All three of the following are valid – they are the same:
• int *ptr;
• int * ptr;
• int* ptr;
• Assigning the address of a variable to a pointer using unary operator (&) which returns the address of that variable.
• Accessing the value stored in the address using unary operator (*) which returns the value of the variable located at the address specified by its operand.