Programming Fundamentals

Interpreters - Interpreted Language​

​Translates and executes program code line by line into machine code.

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ADVANTAGE: Easier to locate and fix errors.​

DISADVANTAGE: Runs slower​

** There are many, many different types of programming languages.

Compilers - Compiled Language​

​Translates, or “compiles” the entire code into machine code and then runs the program, or sets aside to run later.

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ADVANTAGE: Runs faster

DISADVANTAGES: ​Harder to locate and fix errors.​

NAMING RULES

​Basic Guidelines:

• Use descriptive names

• No spaces

• camelCase (Start with lowercase letter and every next word starts with a capital letter)

• Cannot start with a number

• Names are case sensitive!

Data Types

integer - contains a number. The number can be positive, negative, or zero. It cannot have a decimal component. (EX: -50, 0, 5)

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​string - contains text, or a sequence of letters, numbers, punctuation, spaces, etc. (EX: "Hello", world!", "abc123")

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char (short for character) - contains a single character or punctuation. (EX: a, z, 1, !, #)

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Boolean - binary and evaluates to either true or false. (EX: true, false)​

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Variables - can change

​ var myFavoriteNumber = 24;

myFavoriteNumber = 12;

println(myFavoriteNumber);

constant - can NOT change

​ var myFavoriteNumber = 24;

myFavoriteNumber = 12;

How to write a karel command

​ move( );

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• No spaces in commands

• Need to match exact capitalization

• Every command ends in ( );

Functions are a way to teach Karel a new command (word).

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​Functions allow us to

• Break our program into smaller parts

• Make the program easier to understand

• Avoid repeating code over and over

calling "turn around"

Define "Turn around"

​function turnAround() { turnLeft(); turnLeft(); }

​turnAround();

turnRight();

move();​

​Defining a function - Writing out the instructions for this new action

​Calling a function - Actually causing the action to happen

​For Loops - For loops let Karel repeat a section of code a fixed number of times

​While Loops - While loops allow us to repeat a section of 

code as long as some condition is true.

​for(var i = 0; i < count; i++) {

/* code to execute count times */ }

​// This places ten balls down

for(var i = 0; i < 10; i++)

{ putBall(); }

​while(condition) {

/* code to repeat */

}

​while(frontIsClear()) { move();

}

• ALL programming has FOR LOOPS​

• Repeat as long as condition is true.

• Repeat for an undetermined number of times.​

​For Loops

​While Loops

• Repeat fixed number of times

• ​Repeat as long as condition is true

​move( ); five times

to FOR LOOPS

function start ( ){

move( );​

move( );

move( );

move( );

move( );​

}​

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​

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​for (var i = 0; i < 5; i++) {

move( );

}

if/else statements

An if-else statement runs some code if a condition is true, 

and a different block of code if that condition is false.

This IF/ELSE statement tells Karel to move forward if it is clear (nothing blocking his way).

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Else (if something is blocking his way) he will turn left.​

A fixed container that stores an ordered collection of items.

array -

​var shoppingList =

["bread", "eggs",

"milk", "cookies"];

​println(shoppingList)[1] );

Some text here about the topic of discussion

​code - a term used in programming for the set of instructions that can be run or executed by a computer.

​condition - is code that you put inside an if statement or while-loop.

object - can store combinations of keys and values where the value can be accessed by its associated key. Resizable - One data type