Job Ready Java

Lesson 9Understanding Flowcharts and Algorithms

Flowcharts allow us to visualize how the application will flow from one instruction to the next, from start to finish. Building a flowchart before we start to code a program helps ensure that we don't skip any steps in the program itself, as well as giving us a tool to easily communicate those steps to others.

LEARNING OBJECTIVES

By the end of this lesson, you will be able to:

• Explain what an algorithm is
• Describe how developers use flowcharts as part of the software development process
• Identify basic shapes in a flowchart
• Map an algorithm to a flowchart

FLOWCHART BASICS

One of the interesting things about programming is how surprisingly simplistic computers and programs really are. Even though we can create massive-scale programs that perform complex tasks, there are really only three things a program can do.

• Sequence: Execute a series of statements in order
• Branch: Follow a specific path based on a defined condition
• Loop: Repeat a series of instructions until a condition is met

We use the term flow of control to define the path that a program takes from one instruction to the next, and we use a flowchart to visualize the flow of control.

Another important term is algorithm. While TV shows and movies make algorithms sound like very technical things that only a software developer could understand, the term algorithm is really just a well-defined set of instructions that a computer or similar machine can follow to ...