algorithmsWriting instructions in the order they should execute

Creating a method

Exercise 1 • Move the sprite 25 steps,

• Have the sprite say your name for 3 seconds

• Turn the sprite around and move it back where it came from

• Have the sprite say “I love BYOB!” for 5 seconds

Some commands require additional information to execute.

pointInDirection(90);

90 is the argument (value) The are where you put arguments is called parameter( );

Drawing

• Exercise 1: Write an algorithm to make your sprite draw a square with 50 step sides.• Exercise 2: Once

you’ve done that, write an algorithm to draw two squares next to each other• The squares should

not be connected by a line

Sequence

• Exercise: Rewrite your square drawing algorithm to draw a square whenever the space bar is pressed. Clear the screen before each new square.

User Interaction

• Exercise: Write scripts to allow the user to move a sprite around the stage with the arrow keys.

Loops Repeated Instructions • Exercise 1: Rewrite the

script to draw a square using loops. Try not to repeat any code.

• Exercise 2: Now rewrite the script to draw two squares next to each other using loops. Again, try not to repeat code.• This is tricky!

User Input

• Exercise 1: Write an algorithm to do the following:• Ask the user for a number

between 1 and 10• Draw that many squares

• Exercise 2: Write an algorithm to do the following:• Ask the user for a number

between 1 and 10• Ask the user for a number

between 1 and 255• Draw the first number of

squares with the pen color set to the second number

Color • Color has values between 1 and 255

RGB Model for color

Color(r,g,b)

Color(255,0,0) red Color(0,255,0) green Color(0,0,255) blue

Creating Variables • Variables store

information that can change.

•

Create the variable

Must set the variable to some amount

Assign the variable new information

Color • Exercise 2: Write an

algorithm to do the following:

• Ask the user for a number between 1 and 10

• Ask the user for a number between 1 and 255

• Draw the first number of squares with the pen color set to the second number

Arithmetic Operators

• Exercise: Write an algorithm to do the following:• Ask the user for a

number between 1 and 5• Draw twice that many

squares

Boolean expressions evaluate to either true or false

Relational Operators They show a relation between 2 things. 6 < 7 5 > 4 25 == 7 72 <= 52

They are used in conditionals to execute either the if or the else part of nothing.

Boolean Expressions

AND T F

T T F

F F F

OR T F

T T T

F T F

NOT

T F

F T

Compare two complete conditions

Draw a square and a rectangle. --- Must do both AND Draw a square or a rectangle -- Can do either OR Draw a square or a rectangle (NOT)

Conditionals – Booleans Random

• Exercise 1: Write an algorithm to do the following:• Generate a random number

between 1 and 10• Draw a red square if the

number is less than 6• Draw a blue square if the

number is 6 or greater

• Exercise 2: Write an algorithm to do the following:• Generate two random

numbers between 1 and 10• If both are less than 6, draw

a red square• If both are 6 or greater,

draw a blue square• Otherwise, draw a purple

square

Relational Operators

Greater than >Less than <Equal to == >= <=

Project: Create an algorithm that will generate a random number and say the number and whether it is even or odd.

If the random number is even it will say the random number and I am an even number.

If it is odd it will say the random number and I am odd

Procedure: 1. Create a variable called random2. Set the random variable to a random number using the random operator3. Check to see if it is even or odd by creating if statements and using the modulus operator. 4. Create if statements that You will need to use the modulus operator to see if the number is even or odd.

5. Copy your code into a word document.

Create a Guessing Game • Create the Algorithm

You will need to create two variables. guess randomNumber

Use the random number generator from operators group