In the new parser function exp$()$ please have the following line of code at the start of the function:

printf$("$Enter

$")$;

And please have the following line of code immediately before the$$return statement:

printf$("$Exit

$")$;

Part A

Test case $1$: Quadratic formula expression$$ using constants $($a$=1,$ b$=6,$ c$=8).$ You will have to modify the lexical analyzer to accept a floating point fraction:$\mathrm{.}5$ and you may assume for simplicity that the regular expression for a floating point fraction$$ has a decimal point followed by one or more digits. You will also have to allow an to also generate a floating point fraction in the BNF grammar rules:

$6$ ~ $62^41*8*-\mathrm{.}5^+21*/$

Test case $2$:$$ three assignment statements followed by an expression for the quadratic formula:

a $1=$

b $6=$

c $8=$

b ~ b $2^4$ a $*$ c $*-\mathrm{.}5^+2$ a $*/$

Part B

$($sum $+47)/$ total

sum $+(47/$ total$)$

$($sum $+47)*($b $*$ b $-4*$ a $*$ c$)/$ total