# Concepts of Resistor Color Duo

## General

 [Example solution](https://github.com/exercism/ruby/blob/master/exercises/resistor-color-duo/.meta/solutions/resistor_color_duo.rb)

- Classes:
  - Defining classes
- Methods:
  - Defining methods
  - Arguments
  - Return values
- Strings:
  - What is a `String`
- Class methods:
  - How to define a class method

Depending on the approach either:
- Hashes:
  - How to initialize/create a hash
  - How to access it's values

or
- Arrays:
   - How to create an `Array`
   - What are indexes and how can they be useful
   - How to get the index of a value that's stored in an `Array`

### Approach: use string interpolation (positional approach)

- `String` interpolation
- How to get the `Integer` representation of a `String`

### Approach: Using `Enumerable` methods

- Loops:
   - What it is
   - How it works
   - `Enumerable` methods and finding the appropriate one
   - Return value of `Enumerable` methods
- Blocks:
   - What blocks are
   - How to use them with `Enumerable` methods
   - How to chain method calls to blocks
- Arrays:
  - How to take the first `n` elements form an `Array`
- Strings:
  - How to get the `Integer` representation of a `String`

### Approach: `first_value * 10 + second_value`

- No special requirements other than the requirements mentioned in the general section

Add Resistor Color Duo concepts
Add Resistor Color Duo concepts
