Python Algorithms, Pseudocode, and Flow Charts

Algorthims, Flow Charts, and Pseudocode

Python Programming
Fisher Johnson
NCVPS

Vocabulary Related to Algorithms

Algorithm: step by step set of instructions for solving a task.

Stepwise Refinement: the process of breaking the problem down into steps small enough that they can be expressed in code.

Multiple Choice

What is a step by step set of instructions for solving a task.

• Problem Solving Process

• Algorithm

• Program

• None of the above

Three steps of a Program

• • Step 1: Get the required data also called input

  • Step 2: Explain in logical steps how to solve the problem/develop the algorithm

  • Step 3: Report the findings in a usable for or output

Reorder

Reorder the three steps of a program

• Get the required data also called input

• Explain in logical steps how to solve the problem/develop the algorthim

• Report the findings in a useable format or output

1

2

3

• 1
• 2
• 3

Example of Psuedocode

​Psuedocode for a guessing game

Start program
Secret number is 7
Say "Guess the secret number between 1 and 10!"

Wait for your guess

If your guess is 7 Say "Awesome! You guessed it!
🎉" Otherwise if your guess is less than 7 Say "Too low! Try again!
🔻" Otherwise Say "Too high! Try again!
🔺" End if End program

• Pictorial representation of an algorithm

• Shapes and lines represent the flow of the program.

​Flowcharts

• Algorithm written in plain English (or native language)

• No Proper Syntax

• No Working Program

Pseudocode

BEFORE writing code you need to PLAN

​

Parts of a flow chart

Oval-

Rectangle Process/Calculation/Statement

Diamond- Decision making or branching.

​Start or End of a program

​

​

Multiple Choice

Which shape indicates start or end of a program and is mandatory in a flow chart?

• Circle

• Rectangle

• Diamond

Multiple Choice

Which shape indicates a process, statement, or calculation?

• Circle

• Rectangle

• Diamond

Multiple Choice

Which shape indicates a decision making statement?

• Circle

• Rectangle

• Diamond

​More about Flowcharts

1. Order of Algorithm goes from left to right or top to bottom

2. Have a logical start and finish

3. Only one flowline should connect to an oval (terminal symbol)

4. Conditionals (diamonds) should have two answers such as true/false or yes/no

Categorize

Options (16)

Write the program out like you speak

No proper syntax

Write in native language

No working program

Use simple logic to describe steps

Focus on the algorithm rather than syntax

Can be easily understood by non-programmers

May include loops and conditions in plain language

Visual representation of a process

Uses shapes to represent different types of actions

Arrows indicate the flow of the process

Can simplify complex processes

Helps in understanding the sequence of steps

Useful for planning and documentation

Can be created using various software tools

Easily shareable and understandable by teams

Organize these options into the right categories

Pseudocod

Flow Chart

Multiple Choice

In which direction does the order of an algorithm typically flow in a flowchart?

• Bottom to top

• Right to left

• Left to right or top to bottom

• Diagonally

Multiple Choice

What type of answers should a conditional (diamond) symbol in a flowchart have?

• multiple choice options

• True/False or Yes/No

• Only "yes"

• Numeric Values only

Multiple Choice

How many flowlines should connect to a terminal (oval) symbol in a flowchart?

• One

• Two

• As many as needed

• None