Consider the following class of a c$++$ code.$[$Prob$.6.$ Fundamental of Programming$]$

Your answers should be written in Korean or English.

For programming problems, you can assume that all the "include" statements and

"namespace" statements are already written, and you are allowed to omit them.

$(24$p$)$ Consider the following program:

void main$()$

$\{$

int $a=7,c$;

double $b=2\mathrm{.}6,d,$ e;

$c=\frac{a}{2}+0\mathrm{.}6$;

$d=\frac{a}{2}+0\mathrm{.}6$

$e=({\displaystyle \underset{\phantom{}}{\overset{\phantom{}}{}}})(\frac{b}{2}+3\mathrm{.}9)$;

$\}$

Write the values of $c,d,$ and e after the execution of the above program,

and explain why.

$(30$p$)$ Write a $C$ or $C++$ program that receives one alphabet character

among $\text{'}$A$\text{'},\text{'}$a$\text{'},\text{'}$B$\text{'},\text{'}$b$\text{'},\text{'}$C$\text{'},\text{'}$c$\text{'}$ from the keyboard, and output some message

according to the received character. If the character is $\text{'}A\text{'}$ or $\text{'}a\text{'},$ output

"Excellent", and if it is $\text{'}B\text{'}$ or $\text{'}b\text{'},$ output "Good", and if it is $\text{'}C\text{'}$ or $\text{'}$c$\text{'},$

output "Not too bad" If the received character is none of them, repeat the

above procedure again. Your program will repeat this procedure until the

received character is one of the proper character.