Problem Solving and Flowcharts

Problem Solving Aspects

• Problem solving involves several key steps: understanding the problem, formulating a model, developing an algorithm, writing the program, testing the program, and evaluating the solution.

Flowchart

• A flowchart is a diagrammatic representation used for solving logical tasks.
• It uses boxes of varying shapes connected by lines to visually represent the flow of control in a program.
• Flowcharts provide a common method of communication.
• Different symbols are used to depict various actions, decisions, and data.

Flowchart Symbols

• Start/End: Marks the beginning or end of a process, often labeled "start" or "end."

• Action/Process: Represents a single step or a sub-process in a larger process.

• Decision: Indicates a point where a choice must be made, typically represented by a diamond shape.

• Input/Output: Depicts data entering or leaving a system, such as reading input or displaying output.

• Connector: Used to connect different parts of a flowchart where the flow continues.

• Flow Line: Shows the order of steps or the sequence of operations in the flowchart.

• Delay: Indicates a delay in the process.

• Merge: A point where two or more branches of the flowchart come together.

• Collate: Indicates a step arranging information into a standard format.

• Sort: Indicates a step organizing data based on a specific criteria.

• Subroutine: A sequence of actions performing a specified task within a larger process, sometimes needing a separate flowchart.

• Manual Loop: A sequence of commands that repeats until manually stopped.

• Loop limit: The point where a loop will end.

• Data Storage: A step storing data.

• Database: A list of organized information for searching and sorting.

• Display: Data presented.

• Off-Page: Shows the flow continues on another page.

Number Problems

• Flowcharts are used for various mathematical calculations like determining if a number is positive or negative or if a number is odd or even.

Large Number Problems

• Algorithms and flowcharts are used to find the largest number from two or three numbers.

Print 1 to 10

• This algorithm involves initializing a variable ('a') to 1, printing its value, increasing its value, and repeating this until 'a' reaches 10.

Facebook Login

• Flowcharts guide the steps for logging into Facebook, including entering the web address, email, and password. Correct username and password lead to the account; inaccurate information shows a log-in error.

Add 10 and 20

• A flowchart will list procedures for taking the two numbers, and using addition, to arrive at a single number.

Sum of 5 Numbers

• A flowchart can delineate how to calculate the sum, in steps, using a loop-type structure.

I am Great

• A flowchart might illustrate printing (displaying) the text.

Algorithm

• An algorithm is a set of step-by-step instructions that solve a problem or perform a task.
• It's important to consider constraints, inputs, outputs, and the desired solution when creating an algorithm.
• Well-designed algorithms should be precise, unambiguous, and finite.

Designing an Algorithm

• To create an algorithm, you need to define the problem, identify constraints, specify inputs and outputs, and outline the solution given those constraints. This is a needed pre-requisite.

Pseudocode and Algorithm Examples

• Examples illustrate converting feet to inches, calculating area of a rectangle, and converting Fahrenheit to Celsius using pseudocode and algorithms.

Flowcharting Examples

• Flowcharts are shown for solving problems such as finding the largest number from two or three numbers, performing basic arithmetic operations (e.g., calculating the area of a rectangle or square), and simple algorithms like finding the area or perimeter of common geometric shapes (rectangle, square, triangle).
• Methods for calculating simple interest, and finding factorials are also represented.