DEFINE THE PROBLEM

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• DEFINE THE PROBLEM

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Analysis of the Problem

• 1. Determine what is given - input
• gtnouns, adjectives
• 2. Determine what is required - output
• gtnouns, adjectives
• 3. Determine the transformations
  needed(processing)
• -actions needed to produce the required output
• gtverbs, adverbs

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Inputs and Outputs

• Determine data that is input to the problem, data
  that will be output from the problem
• Nouns
• We call the input and output data-variables
• We use a particular naming convention
• No spaces
• Meaningful names
• Usually begin with lowercase
• Examples roomWidth, numPeople, studentName

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Example 1
Read three numbers, add them together and print
the total. Read three numbers, add them together
and print the total. Step 1 define inputs and
outputs(hint look at nouns) Break up several
values into separate variables
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Example 1
Read three numbers, add them together and print
the total. Read three numbers, add them together
and print the total. Step 2 define list of
actions. Hint Use verbs,these steps usually
involve the input and output defined in step 1
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Example 2
Write a program to prompt the operator for the
maximum and minimum temperature readings on a
particular day, accept those readings as
integers, and calculate and display on the screen
the average temperature.
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Example 2
Write a program to prompt the operator for the
maximum and minimum temperature readings on a
particular day, accept those readings as
integers, and calculate and display on the screen
the average temperature.
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• PLAN THE SOLUTION

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Plan the Solution

• Outline the Solution
• Major processing steps involved
• Major subtasks
• Major control structures
• Major variables and record structures
• Mainline logic
• Develop the outline into an algorithm
• Test the algorithm for correctness

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Structured Programming

• Top Down Design Development
• Modularity
• Control structures
• sequence
• selection or IF-THEN-ELSE
• repetition or looping

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Design/Plan the solution

• Algorithm a step by step procedure for solving
  a problem
• Programs - implementations of algorithms
• Set of instructions
• flowcharts
• pseudocode
• test solution for correctness - trace

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Pseudocode

• structured concise English statements used to
  state operations
•  language independent,no standard
•  use words and phrases that are in line with
  basic computer operations
•  

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Pseudocode

• Write statements in simple English
• Write each instruction on a separate line.
• Use keywords and indentation for control
  structures.
• Write instructions from top to bottom, with only
  one entry and one exit.
• Groups of statements may be formed into modules.

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Pseudocode

•  1. Input - receiving information
•  keywords - Read, Get, Input
•  Read - receive information from a record on a
  file
• Get - receive information from the keyboard.
• Read studentName
• Get systemDate
• Read num1,num2
• Get taxCode
•  use one verb followed by one or more nouns

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Pseudocode

• 2. Output
• putting information out
• Put, Output,Display - screen
• Print - printer
• Write - file
• Print smaller.
• Print "Program Completed"
• Write customer_record to file
• Output totalTax
• Display "End of Data"

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Output continued

• Labels
• Display "label"
•  statement inside quotes is printed as it appears
• Display "x" // if x 5
• Yields x
• Display x
•  yields 5
•  Display "X " and x
•  yields X 5

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Pseudocode

• 3. Arithmetic
•  use name of the operation or algebraic symbol
•  add,subtract,multiply, divide, exponentiation
•   - /
•  x algebraic expression
• count count 1
• netPay hourlyPayRate hoursWorked
• salesTax cost 0.10
• totalPrice price salesTax

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Pseudocode

• 4. Assignment - place information into a storage
  location
•  Initialize, Set - give variable initial value
• Save,Store - save info for later
•   //preferred
• y 3 note does not mean equality
• could involve calculation
• area length width
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