6.19 Programming Project #2:
Vectors and Arrays
Background
The standard C++ library contains a container class called vector. The vector class
works very much like lists in C#, Java, and other languages. In C++, generic collection
classes are created using “templates”, which we’ll see at the end of the course.
Objective
At the completion of this project, you will have created an application that:
• Gets a variable amount of input from the user,
• Uses a vector to store data, and
• Uses functions that you wrote.
Project — Find the Median and Record the
Grade
Professor Dolittle has asked some computer science students to write a program that
will help him calculate his final grades. Professor Dolittle gives two midterms and a final
exam. Each of these is worth 100 points. In addition, he gives a number of homework
assignments during the semester. Each homework assignment is worth 100 points.
At the end of the semester, Professor Dolittle wants to calculate the median score on
the homework assignments for the semester. He believes that the median score is a
good measure of the student’s overall performance on the homework assignments. The
median is found by putting the homework scores in order, and then taking the score
that is at the midpoint of this list. If there are an odd number of assignments, the
median is the score exactly in the middle of the list. If there are an even number of
assignments, the median is the average of the two scores closest to the midpoint of the
data.
Once the median score is known, professor Dolittle takes the sum of the exam scores
and the median homework score and uses this value to compute a letter grade. The
sum is is truncated to the next integer down if it has a fraction (so 180.7 is a 180 for
grading purposes). Letter grades are assigned based on the following table:
Program Requirements
Your program should work as follows:
1. All user input should be tested to be sure that it is a valid integer value in the
range 0 to 100.
2. It should ask the user to enter in the score for the first midterm. Then this value is
read in and saved.
3. It should ask the user to enter in the score for the second midterm. Then this
value is read in and saved.
4. It should ask the user to enter in the score for the final exam. Then this value is
read in and saved.
5. The program then asks the user to enter in the scores for the homework
assignments. Any number of scores can be entered in. You will test for a -1
entry to stop adding to the vector.
6. Store the homework scores in a vector.
7. Once all of the data has been entered, the program calls a function that you
have written to find the median homework score.
8. The program then calls a function that you have written to calculate and return
the letter grade. The return grade is based upon the total of the three exams
plus the median homework score (total points).
9. Finally, display the median homework score, the total point count, and the letter
grade.
Dr. DoLittle’s Grading Program …..
Please enter in the score for the first exam: abc
Sorry, your input must be an integer. Please try again.
Please enter in the score for the first exam: 97
Please enter in the score for the second exam: 65
Please enter in the score for the final exam: 85
Enter the score for a homework assignment: abc
Sorry, your input must be an integer. Please try again.
Enter the score for a homework assignment: 200
Sorry, your input must be between 0 and 100. Please try again.
Enter the score for a homework assignment: 99
Enter the score for a homework assignment: 65
Enter the score for a homework assignment: 78
Enter the score for a homework assignment: 80
Enter the score for a homework assignment: -1
The median homework score was 79
The total points earned was 326
The letter calculated letter grade is B
As a reminder, you need to place all input at once into the input window in Zylabs. For
the example above, the input is:
abc
97
65
85
abc
200
99
65
78
80
-1
