Parsers often use lexers to break the input string into a sequence of lexical tokens such as

identifiers, numbers, operators, strings, etc.

Construct an FSA that recognises identifiers, numbers, and strings as defined below. For the

purposes of this question, the alphabet of the language is $=\{a,b,0,1,..{?}^{\text{'}\text{'}},\}($the ${?}_{}$ symbol

represents a space symbol$).$

identifier starts with a letter and is followed by any number of letters or numbers $($e$.$g$.,$ a$1,$ ab$)$;

number consists of $1$ or more digits optionally followed by a period and $1$ or more digits $($e$.$g$.,$

$10,0\mathrm{.}11$

string starts with a double quote $("),$ which is followed by any number of characters different

from a double quote and finishes with another double quote $($e$.$g$.,"","$a$""$ab$","$a$01","10",$

$"$a$\_$b$","$a$.$b$1").$