A single character may be written as a single quote immediately followed by
that character. Some backslash escapes apply to characters, \b,
\f, \n, \r, \t, and \" with the same meaning
as for strings, plus \' for a single quote. So if you want to write the
character backslash, you must write '\\ where the first \ escapes
the second \. As you can see, the quote is an acute accent, not a grave
accent. A newline
immediately following an acute accent is taken as a literal character
and does not count as the end of a statement. The value of a character
constant in a numeric expression is the machine's byte-wide code for
that character. as assumes your character code is ASCII:
'A means 65, 'B means 66, and so on.