Constant Variables

Constant variables in C++ are variables whose values cannot be altered after they are set. By using the const keyword, a variable becomes read-only, preventing accidental modification. Constants are especially useful for defining values that should remain consistent throughout the program, such as mathematical constants (e.g., PI) or configuration settings.

Syntax

const data_type variable_name = value;

• data_type: The type of the variable.
• variable_name: The name of the constant variable.
• value: The initial value assigned to the variable. Once set, this value cannot change.

Example

This example demonstrates how to declare and use a constant variable in C++:

#include <iostream>

int main() {
    const int max_attempts = 5;
    std::cout << "Maximum allowed attempts: " << max_attempts << std::endl;

    // Uncommenting the following line would cause a compilation error
    // max_attempts = 10;

    return 0;
}

This example results in the following output:

Maximum allowed attempts: 5

In this example, max_attempts is declared as a constant integer. Attempting to modify it later in the code would result in a compilation error, ensuring that its value remains consistent.

Codebyte Example

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