case label does not reduce to an integer constant.
Description
Case expressions must be integer constants.
Example

Output

How to fix it ?
Case expressions must be integer constants.
syntax
switch (< expression of integer type>) { case <integer onstant-expression> : statement(s); break; /* optional */ case <integer onstant-expression> : statement(s); break; /* optional */ /* you can have any number of case statements */ default : /* Optional */ statement(s); }
See also