From the textbook: Big C$++$: Late Objects, Enhanced:

E$7\mathrm{.}3$

Write a function that returns a pointer to the maximum value of an array of floating$-$point data:

double $*$ maximum$($double $*$ a$,$ int size$)$

If size is $0,$ return nullptr.

P$7\mathrm{.}8$

Define a structure Student with a first name,last name and course grade$($A$,$B$,$C$,$D$,$ or F$).$ Write a program that reads input in which each line has the first and last name and course grade separated by space. Upon reading the input, your program should print all students with grade A$,$ then all students grade B and so on$.$

Sample Output:

Enter the Student first name and last name, grade, please leave space

Allan James F

Richard John A

James Allan F

Ethan Clark B

John James D

Peter John C

John Peter A

Initial list:

F Allan James

A Richard John

F James Allan

B Ethan Clark

D John James

C Peter John

A John Peter

Students sorted by grade:

A Richard John

A John Peter

B Ethan Clark

C Peter John

D John James

F James Allan

F Allan James

E$8\mathrm{.}5$

Write a program that reads each line in a file, reverses its characters,

and writes the resulting line to another file. Suppose the user specifies

input.txt and output.txt when prompted for the file names, and input.txt

contains the lines

Mary had a little lamb

Its fleece was white as snow

And everywhere that Mary went

The lamb was sure to go$.$

After the program is finished, output.txt should contains

bmal elttil a dah yraM

wons sa etihw saw eceelf stI

tnew yraM taht erehwyreve dnA

$.$og ot erus saw bmal ehT

P$8\mathrm{.}6$

Write a program that reads the country data in the file how$\_$to$\_1/$worldpop$.$txt $($included with the book$$s source code$).$ Do not edit the file. Use the following algorithm for processing each line. Add characters that are not white space to the country name. When you encounter a white space, locate the next non$-$white space character. If it is not a digit, add a space and that character to the country name, and keep adding characters until the next white space. If a white space is followed by a digit, unget it and read the number. Print the total of all country populations $($excepting the entry for $$European Union$).$ Please download the worldpop.txt word file from the announcement.