When would you use a constant class?

Answer 1

i guess it is when you know definitely that the variable within should not be changed.

Answer 2

when you dont want the user to change the variables within

Answer 3

we use a constant class when we want that the value does not change in the whole program.
Ex: const float pi = 3.14;
Here the variable named 'pi' does not changes its value in the whole program, though you want to change.
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