UTPA STEM/CBI Courses/Computer Science/Repetition

From Wikiversity
Jump to navigation Jump to search

Course Title: Computer Science I

Lecture Topic: Repetition structure

Instructor: Gustavo Dietrich

Institution: UTPA

Backwards Design[edit | edit source]

Course Objectives

  • Primary Objectives- By the next class period students will be able to:
    • Understand the advantage or necessity of using repetition structures to solve certain type of problems
    • Recognize the categories and subcategories of loops (counter-controlled vs. event-controlled; eof,sentinel,flag)
    • Understand the structure of loops (initialization of loop controller, testing of loop controller, updating of loop controller, body of the loop)
    • Understand how different repetition structures work (pre-test vs. post-test)
    • Write C++ code to implement the different repetition structures (while, for, do-while)
  • Sub Objectives- The objectives will require that students be able to:
    • Create logical and relational expressions
    • Identify syntax and logical errors in repetition statements (the semicolon after the loop’s heading, the use of curly braces to specify a block of statements, wrong placement of the statement updating the loop controller, etc.)
  • Difficulties- Students may have difficulty:
    • Understanding the underlying concepts involved in looping (use analogies)
    • Understanding when and how to use loops when given a problem (use analogies)
    • Creating complex conditional expressions
  • Real-World Contexts- There are many ways that students can use this material in the real-world, such as:
    • Any of those situations that require the repetition of actions to solve a problem. For example,
      • Mathematical field: calculation of sin x, Euler’s value e, greatest common divisor, etc.
      • Business field: calculation of an average, validation of a password/user name combination, etc.
      • Engineering field: calculation and displaying of the trajectory of a projectile, filling of a table with values read from a sensor, etc.

Model of Knowledge

  • Concept Map
    • Analysis of problem, requires
      • Critical thinking skills
      • Summarizing skills
    • Design of solution (algorithm design), requires
      • Problem decomposition skills
      • Understanding of underlying programming concepts
        • Data types
        • Sequence
        • Control structures
          • Selection
          • Repetition
        • Modular programming (functions)
        • Arrays
        • Abstract data types
          • Structures
          • Classes
        • Pointers
        • Data structures and algorithms
          • Trees
          • Searching
          • Sorting
      • Use of design tools -- pseudo code writing skills
    • Implementation of solution
      • Tools of the trade
        • Learned in Lectures through
          • Slides
          • Analogies
          • Sample programs
          • Group exercises
        • Using C++ to implement underlying concepts (listed above)
        • Applying underlying concepts, covered in lectures using
          • In-class exercises
          • Lab assignments
          • Homework assignments

  • Content Priorities
    • Enduring Understanding
      • Have analysis skills
      • Have design skills ( includes knowledge of pseudo code)
      • Know Control Structures
        • Sequence
        • Module
        • Selection
        • Repetition
      • Know C++ syntax rules
    • Important to Do and Know
      • Know how to use software development tools like MS VC++
      • Team work skills
    • Worth Being Familiar with
      • Time management

Assessment of Learning

  • Formative Assessment
    • In lectures:
      • Asking questions to the students and providing feedback after their reply (informs me and them)
      • Asking the students to discuss with their partner the answer to a question or a topic just covered (informs them)
      • Developing a program on the screen with the students’ collaboration (informs me and them)
    • In their own time:
      • Asking the students to use a software tool that presents them multiple choice questions and the corresponding feedback after their answer (informs them)
      • Asking the students to use the study guide provided a week before each test to self-evaluate their knowledge (an answer key is provided the day before the test) (informs them)
  • Summative Assessment
    • In labs/home:
      • Lab assignments for assessing their knowledge of the programming language syntax
      • Homework assignments for assessing their problem solving skills
      • Tests
        • MC T/F for assessing their knowledge of the concepts taught
        • Assessment questions in test to evaluate them individually

Legacy Cycle[edit | edit source]


By the next class period, students will be able to:

  • Solve problems that require the use of loops

The objectives will require that students be able to:

  • Analyze the problem
  • Design the solution using pseudo code
  • Recognize the type of repetition structure required to solve the problem
  • Implement the algorithm using C++


Calculating the average temperature of the McAllen-Mission-Edinburg-Pharr metropolis would not be difficult since you would need to sum up only four temperatures. But how would you calculate the average temperature of the whole planet?


  • Grab a calculator and imagine you have to determine the average temperature of the whole planet. List the steps that you would take to do this
  • Is this a repetitive task?
  • How many values do you process at a time? Can you process hundreds of them in just one step?
  • Do you know how many values you need to process in total?
  • Where would you expect to get the data from?
  • Would you do any validation?


  • Discuss the problem with your partner
  • Look for possible solutions in the textbook
  • Search the web to find out what is done in the real world


  • Same as above


  • Discuss with your partner a possible solution for the problem
  • Create the algorithm and walk through it
  • Run my sample solution and check if the results are what you expected from your algorithm walk through


  • Write a program that reads the temperatures from a file and determine the average (group evaluation)
  • Answer the assessment questions at the end of the test (individual evaluation)

Pre-Lesson Quiz[edit | edit source]


Indicate whether the statement is true or false. When you are finished making your selections, click the "Submit" button.

1 Loop control variables are automatically initialized in a loop.


2 Assume all variables are properly declared. The output of the following C++ code is 2 3 4 5.

n = 1;
while (n < 5)
   cout << n << " ";


3 The control variable in a flag-controlled while loop is a bool variable.


4 The do...while loop has an exit condition but no entry condition.


Test Your Mettle Quiz[edit | edit source]

Multiple Choice

Identify the choice that best completes the statement or answers the question. When you are finished making your selection, click the "Submit" button.

1 Loops are called post-test loops.


2 Consider the following code. (Assume that all variables are properly declared.)

cin >> ch;
while (cin)
   cout << ch;
   cin >> ch;