Midterm Exam, CSCI 330, Fall 2020

• The weight for each question is given.
• Please answer each question thoughtfully and carefully.
• Please use a word processor to answer the questions.
• Please label your answers with the question number and part.
• Please answer each question thoughtfully and carefully. I expect your answers to demonstration participation in this class.
• You may use books, notes and other non-human references. You may not interact with any other person when answering these questions.
• Proper use of terminology will be graded.
• The test is due at the end of class.
  • Submission instructions are at the end of the test.
  • Submissions should be done through the D2L assignment folder Test 1
  • If you have problems submitting the test, please contact your instructor.
• If you have questions, please communicate with your instructor via email.

1. Relationships: for the relationships Shared Aggregation, Composition, Inheritance.
   • [3 points] Describe each.
   • • Shared Aggregation
       • Shared Aggregation is a "has-a" relationship where either entity can exist without the other.
       • The larger entity is composed, at least in part, of the smaller entity.
     • Composition
       • Composition is a "has-a" relationship where if the larger entity is destroyed, the contained entity is destroyed as well. The items can not exist without each other.
       • The larger entity is composed, at least in part, of the smaller entity.
     • Inheritance
       • Inheritance is a "is-a" relationship. In this case one entity is a specialization of another.
   • [6 points] Give an example of each. Explain why your example illustrates the relationship.
   • • Shared Aggregation
       • A pond has-a frog.
       • Frogs can be in ponds, ponds can contain frogs
       • While a pond can contain a frog, the frogs are free to move in and out of a pond. If the pond is destroyed, the frog is not necessarily destroyed.
     • Composition
       • A frog has-a heart.
       • The heart is a component of of a frog.
       • If the frog is destroyed, the heart is destroyed as well.
     • Inheritance
       • A frog is-a amphibian
       • Amphibians have
         • a common set of properties cold-blooded vertebrate animal.
         • a common set of behaviors
       • A frog is an amphibian with
         • A frog has all properties and behaviors of an amphibian.
         • In addition, a frog has frog like behaviors and properties.
   • [3 points] Create a UML diagram for each of your relationships.
   • • Shared Aggregation
       • 
     • Composition
       • 
     • Inheritance
       • 
2. Object Design
   • [2 points] What criteria should be employed when deciding if something should be an object during the design phase?
   • An object should have both behavior and properties.

     Objects should have clear boundaries and responsibilities.

   • [4 points] Give an example of two items which would not qualify as an object. Give the reason that each does not qualify as an object. The reason for disqualification for each should be different.
   • A single data item is not an object. It has a property but no behaviors.

     An algorithm is not an object. It has behavior but no properties.
3. [4 points] Describe the ADT vector. List domain and operations.
   The domain of a vector is 0 or more items of the given type. These items are maintained in the "locations" they are inserted. Operations on a vector include:

   • Adding elements to he end of the vector(push_back)
   • Indexing into a vector ([])
   • removing elements from a vector (erase).
   I am simply checking to see if you can provide a reasonable list of operations on a vector, it does not need to be exhaustive, alto you could achieve that with a simple copy and paste from cplusplus.com.
4. Iterators
   • [2 points] What is the purpose of an iterator in the STL?
     An iterator provides a standard way to access elements of a container in the STL.
   • [2 points] Describe the various types of iterators. Why do these types exist?
     Standard iterators can be modified with any of the following properties

     • reverse
     • constant

     Reverse iterators allow the programmer to traverse from the "end" of the container to the beginning of the container

     Constant iterators allow the programmer to traverse a container that has been declared constant.

   • [2 points] Describe the operations that can be performed on an iterator.
     • Iterators can be assigned.
     • Iterators can be compared.
     • Mathematical operations (increment, decrement) is supported on iterators.
     • Iterators can be dereferenced.
5. [4 points] Describe the operation of the new [] operator in C++.
   New allocates memory on the heap and returns a pointer to that memory. This is specifically for the creation of an array of items as new[n] will allocate n locations big enough to hold an instance of the item type given.

   If the the item being created has a constructor, the constructor is called.
6. Unit testing
   1. [2 points] What is a unit test?
      A unit test is a test which tests the behavior of an individual unit or section of software.
   2. [2 points] How can implementing unit tests during the design process improve the final product?
      By designing unit tests early in the software design process the designer may

      • Gain better insight into the requirements for the unit under design.
      • Gain a better understanding of special cases for the unit under design.
      • Helps provide a measurement of when the code is complete.
   3. [2 points] How can a test framework improve the software development process?
      • They provide assistance with design (see above)
      • They provide evidence that the code is working.
      • They provide a tool for locating and correcting bugs in later product development.
      • They provide examples of code use.
   4. [2 points] Describe how unit tests evolve during the software development process.
      Test should be developed to test for a robust set of conditions.

      As additional conditions are discovered during testing or use, these should be added to the unit test suite.

7. [10 points] Complete the following program.
   • wordCount.cpp
   • words.dat a data file.
   • You only need to add code where indicated by the comments.
   • You may assume all input is correct and in the proper form. There is no need to change the input.
   • You should use functions from the algorithm library when indicated. Do not write additional functions for this problem.
   • The output for this program should be

              a         1
              b         2
              c         3
              d         4
              e         5
              f         1
              g         1
              h         1
             

   Please see wordCountAnswer.cpp
       

Submission Instructions

• Submit your test and the source code for the program to the appropriate D2L assignment folder Test 1 by 5:45.
• If you miss this deadline, you can submit your test by email to dbennett@edinboro.edu. Depending on the circumstances, there may be a 5% penalty per minute applied for email submissions.