✏️ Explanatory Question
In C programming, a constant is a fixed value that does not change during the execution of a program. Constants are also commonly referred to as literals because they represent values that are directly written in the source code.
A constant can represent different types of values, such as an integer, floating-point number, character, or string. Constants are useful when a program needs to work with values that should remain unchanged throughout its execution.
100
3.14159
'A'
"Hello"
In the above examples, 100 is an integer constant,
3.14159 is a floating-point constant, 'A' is a
character constant, and "Hello" is a string literal.
const Keyword
In C, the const keyword can be used to declare an object whose
value should not be modified through that identifier after initialization.
For example:
const int MAX_MARKS = 100;
Here, MAX_MARKS is declared as a constant with an initial value
of 100. Attempting to assign another value to it is not allowed:
MAX_MARKS = 200; // InvalidC supports constants of different forms and data types. For example:
int age = 25;
float pi = 3.14159f;
char grade = 'A';
The values 25, 3.14159f, and 'A'
are constants (more precisely, literals) used to initialize the variables.
Constants make programs easier to understand and maintain. When a value represents an important fixed quantity, giving it a meaningful name makes the program more readable and reduces the chance of accidentally changing that value.
For example, instead of repeatedly using the value 3.14159,
we can define:
const float PI = 3.14159f;
The identifier PI can then be used wherever the fixed value of
pi is required.
A const-qualified object in C should not be described as
completely identical to a compile-time constant in every context. The
const keyword mainly specifies that the object is not
modifiable through that identifier. C also provides other forms of
constants, such as integer constants, floating constants, character
constants, enumeration constants, and string literals.
A constant is a fixed value used by a program that is not intended to be changed. Constants help make programs more readable, reliable, and easier to maintain.
Variable: A named storage location whose value can be
changed.
Constant: A fixed value or non-modifiable object, depending
on the form of constant being discussed.