LexYacc

Install Lex and Yacc (if not already installed)

sudo dnf install flex byacc(fedora)

Compile Lex and Yacc files

lex arthmetic.l

yacc -d aruthmetic.y

cc lex.yy.c y.tab.c 

Run

./a.out

Clean up (optional)

rm lex.yy.c y.tab.c y.tab.h

Install Flex (if not already installed)

sudo dnf install flex

Compile Lex file and link with Flex library

lex count.l

gcc lex.yy.c -lfl -o word_count

Run the resulting program

./word_count