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➢ What is a problem Analysis
All make decisions on a daily basis.
- What should I have for breakfast?
Where should I go this?
??weekend?
Every time we make a decision. After making this decision, over act on it.Thus,
decision-making is a two-step process.
1. Deciding what to do
2. Taking an Action
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We can divide the problem into smaller
segments. This will make it easier to solve the
problem.
➢ Problem Analysis Method
To Analys a problem we can classified three components.
1. ………………………………………………………………………………….
2. ………………………………………………………………………………….
3. ………………………………………………………………………………….
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For example,
let us consider an invoice issued by a ABC Bookshop. To calculate the price
(amount) of each item, number of items and unit price are required.
First, we should be identified
Input, Process and Output
Input -
Process -
Output -
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Example 1
Find the cost of purchasing five pens
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➢ What is a control structure?
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❖ There are three type of control structure such as,
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3.
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➢ What is a sequence control structure?
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Ex – climbing up or down step by step when going on
stairs case
Ex – students’ study from
grade 1 to 11 continuing
Example -
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➢ What is a selection control structure?
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Example -
Consider a rainy day,
If it rains students are asked to question?
➢ asked to go to the library?
➢ it does not rain, asked to go to the playground.
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Consider a scenario where 10 marks are awarded to the correct answer
Before marks are awarded, it must be checked whether the answer is correct or
wrong. If the answer is correct, 10 marks are awarded. Incorrect answers are
awarded no marks.
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➢ What is a repetition control structure?
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Ex – a class teacher marking the attendance
register
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➢ What is Flow Chart?
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➢ What is a Scratch program and Scratch Interface
SCRATCH is an Open-Source Visual Programming
Language produced to make programming easier to
learn and your own interactive stories animations,
games, music, and art.
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Scratch components
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➢ We can sprites (cat image) move 10 steps forward using Move –Steps in the Blocks
Palette and dragging it onto the Scripts Area.
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➢ Turn …. Degrees
1. Rotate clockwise 15 degrees 2. Rotate anticlockwise15 degrees
• Sprites
➢ The sprite move by (10) to the right change x by a positive number.
➢ The sprite move by (10) to the right change x by a negative number.
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➢ Control Tools
• When. Clicked
- When the green flag is clicked do the following steps
• Wait..secs - It does nothing for 1 second. Go to the next step after 1 second
➢ Practical Example
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Variable
➢ What is a variable?
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What is a Variable name?
The names you give to computer memory locations
which are used to store values in a computer program.
Ex - length, width, marks, height, score, count, total
➢ Create Variable in Scratc
- There are two buttons displays in the block Blocks Palette. When clicked on the
variable block, the following image will be shown
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• When clicked Make a variable in the Blocks Palette the following dialog box will be
displayed.
- For all sprites: Create a new variable that all sprites can see (Such as Marks)
- For this sprite only: Creates a new variable that only this sprite can see
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➢ What is a errors?
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Type of Errors
• Syntax Error
• Semantic error
• Logical error
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• Semantic errors:
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Two types of selection control structures can be used in developing Scratch programs
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Ex -
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➢ What is a comparison Block?
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1. Check whether the value on the left is smaller than the value of the right.
2. Check whether the value on the left equals to the right.
3. Check whether the value on the left is greater than the one on the right.
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There are three types of logical blocks as follows
instruction blocks are used to combine comparison
instruction blocks.
The decision is taken after
comparing the two values
instruction blocks.
1. AND
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2. OR
3. NOT
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