OfTheDelmer

Intro to Web Application Frameworks

First Principles with Sinatra

OBJECTIVE
We will use the concepts discussed in client-server model and request-response handling in a simple web application, use our first web application framework, and be able to build a simple web application.

Self-Assesment

OfTheDelmer

# Classes and Objects
## Code Along


	
	story_hash = {
		"question" => "Welcome to the haunted hotel. What room would you like to go into?",
		"room 1" => "you're dead",
		"room 2" => { "question" => "You picked a good room. What would like to do?",
					  "sleep" => "You're rested for the morning",

OfTheDelmer

Intro to Classes

Methods, Variables, and All That

Learning Objectives

• Understand difference between obbjects and classes
• Understand how objects are referenced
• Understand getters and setters
• Understand attr_writer, attr_reader, attr_accessor
• Understand instance variables and instance methods

OfTheDelmer

#takes two squares 




def check_square(square)
	if(square[0][0] > square[1][0])
		puts square
		square[0][0], square[1][0] = square[1][0], square[0][0] 
	end

OfTheDelmer

class BinTree

	attr_accessor :left, :right, :val
	
	def initialize(val)
		@left = nil
		@right = nil
		@val = val
	end

OfTheDelmer

class BinTree

	attr_accessor :left, :right, :val
	
	def initialize(val)
		@left = nil
		@right = nil
		@val = val
	end

OfTheDelmer

Exercises/Lab for Linked Lists

1.) Write a function called last that finds the last node in the list.

2.) Write a function called count that gets the length of linked list. Don't use the #count method.

3.) Write a function called average that sums a linked list of numbers and divides it by the length.

4.) Write a function to reverse a linked list.

OfTheDelmer

###
#        Node List
###
 
class Node
        attr_accessor :val, :next
        def initialize(val, next_ref =nil)
                @val=val
                @next=next_ref
        end

OfTheDelmer

###
#        Node List
###

class Node
        attr_accessor :val, :next
        def initialize(val,next=nil)
                @val=val
                @next=next
        end

OfTheDelmer

class Node
    attr_accessor :data, :next

    def initialize(data=nil)
        @data = data
    end
end