Chapter 5: Algorithms and Programming Part 2

Programming

• Programs can be developed for creative expression, to satisfy personal curiosity, to create new knowledge, or to solve problems (to help people, organizations, or society).

• Advances in computing have generated and increased creativity in other fields.

Programs Can Be Flexible

• When it was targeted to a smaller, local audience simply to satisfy Zuckerberg’s personal curiosity and enjoyment, Facebook was held to much different standards in its development.

• When it was made for billions of people to use, changes had to be made to accommodate so many people and to target it toward a wide market of people that might use it—making it appealing to a wider audience.

Programming Design Steps

• The first step in programming is planning and identifying programmer and user concerns that can affect the solution.

• Consultation and communication with program users are important aspects of program development to solve problems.

• When designing a large program, an iterative process helps with correctly coding.

Program Documentation

• Program documentation is helpful in all stages of program development.

• Documentation does not slow down run speed and is necessary when collaborating or programming alone.

• Documentation is useful during initial program development and when modifications are made.

Flowcharts

• A flowchart is a way to represent an algorithm visually.

LISTS

• Lists are an organized and formatted way of storing and retrieving data.

• Each element in a list can be accessed by its index.

Traversing a List

• Traversing a list means that you are accessing all the elements of the list one by one.

Procedures

• A procedure is a set of code that is referred to by name and can be called (invoked) at any point in a program simply by utilizing the procedure’s name.

• In some languages, a procedure could be called a method or subroutine.

• The purpose of the above procedure is to append all negative numbers in aList into bList.

• Line 3 iterates through aList.

• If the element in aList is less than 0, line 5 causes the element to be appended into bList.

• A call to keepPositive(aList, bList) where aList[2, −5, −11, 6] and bList[ ] would result in bList containing the numbers [−5, −11].