6.9 Programming Exercises

Exercise 6-1: A professor generates letter grades using Table 6-3.

Table 6-3. Grade values

% Correct	Grade
0-60	F
61-70	D
71-80	C
81-90	B
91-100	A

Write a program that accepts a numeric grade and displays the corresponding letter grade.

Exercise 6-2: Modify the previous program to print out a + or - after the letter grade based on the last digit of the score. The modifiers are listed in Table 6-4.

Table 6-4. Grade-modification values

Last digit	Modifier
1-3	-
4-7	<blank>
8-0	+

For example, 81=B-, 94=A, and 68=D+. Note that an F is only an F; there is no F+ or F-.

Programmers frequently have to modify code that someone else wrote. A good exercise is to take someone else's Exercise 6-2 and modify it.

Exercise 6-3: Given an amount less than $1.00, compute the number of quarters, dimes, nickels, and pennies needed.

Exercise 6-4: A leap year is any year divisible by 4 unless it is divisible by 100, but not 400. Write a program to tell whether a year is a leap year.

Exercise 6-5: Write a program that, given the number of hours an employee worked and her hourly wage, computes her weekly pay. Count any hours over 40 as overtime at time-and-a-half.