, , and are fundamental concepts in computer programming. A variable is a named storage location that can hold a value which can change during program execution. Conversely, a constant is a value that remains unchanged throughout the program. Both variables and constants are used to store data of various data types. Data types are the classification of values that a variable or constant can hold, such as integers, characters, or Boolean values.
The of a variable or constant involves specifying its name and data type. This step allows the computer to reserve memory for storing the value. Once declared, variables and constants can be assigned values using the operator. This operator assigns a specific value to a variable or assigns a value to a constant.
The of a variable or constant determines where in the program it can be accessed. A can be accessed from anywhere within the program, whereas a is only accessible within a specific block of code, such as a function or loop. It is essential to understand the scope of variables and use it appropriately to avoid naming conflicts and unintended changes to data.
A is an expression whose value cannot be changed. It is evaluated at compile time, and the result remains constant throughout the program's execution. The use of constant expressions can enhance code readability and help prevent unintended modifications to critical values.
is a feature in some programming languages where the compiler can automatically determine the data type of a variable or constant based on the assigned value. This feature eliminates the need to explicitly specify the data type, reducing the amount of code and making it more concise.
Keywords
constants | local variable | scope | constant expression | assignment | type inference | declaration | global variable | variables | data types |