Algorithms/Technical Interviewing Workshop - March 13, 2017

Women Who Code - East Bay Gist link bit.ly/wwcberkeley

What is the Algorithms/Technical Interviewing Workshop?

Every two weeks, I lead technical interviewing/algorithms workshops with Women Who Code - East Bay. The workshops are held every other Monday at NextSpace, right next to downtown Berkeley BART. For more information or to sign up, visit the Women Who Code East Bay Meetup page.

1. Introduction & overview

People are working on games, image processing, nails, leading workshops, and React.

2. What does a technical interview look like?

Watch the last section on **Technical Interviewing Techniques**
*This is a free online course that covers the most common algorithm and data structure questions, as well as technical interviewing skills.*
1.  https://classroom.udacity.com/courses/ud513/lessons/7707710408/concepts/77114606610923#

3. Big O (Go over gist)

This a gist on the basics of Big O.  What is the motivation for using it?  What is the Big O of some common built-in methods?
1. https://gist.github.com/abruckman/2d54844e164a4ae17f3082a4a12480b5

4. Problem: mode of array

1. Frequency Hash
    *Level: Warm-up for everyone and for beginners*
- Your goal is to loop through the array only **once**

```ruby 
##Make a frequency hash that counts how many times a name appears in an array.

# freq_hash(["Eric", "Eric", "Kat", "Kat",  "Linda", "Kelly", "Dani", "Kelly", "Julissa", "Kat", "Kelly", "Dani", "Kat", "Kat"]) 	=> {"Eric"=>2, "Kat"=>5, "Linda"=>1, "Kelly"=>3, "Dani"=>2, "Julissa"=>1}
```

Answer: https://repl.it/GToA/2

Challenges that use a frequency hash:

Suggested: use repl.it for coding

2. Mode of Array (Easy)
    For an array of numbers, return the mode of the array.

3. [Lonely Integer](https://www.hackerrank.com/challenges/lonely-integer) (Easy)
	For an array of numbers, repeat the only number that has no pairs in the array.

4. [Sort characters by frequency](https://leetcode.com/problems/sort-characters-by-frequency/#/description) (Medium)
"Given a string, sort it in decreasing order based on the frequency of characters." 

5. [Valid Anagrams](https://leetcode.com/problems/valid-anagram/#/description) (Easy)
"For two words, return true if they are anagrams."

Resources Shared:

Big O Cheatsheet: http://bigocheatsheet.com/
Big O Gist: https://gist.github.com/abruckman/2d54844e164a4ae17f3082a4a12480b5
[RUBY] Double nested and frequency hash example: https://repl.it/GToA/2
[JS] Double nested and frequency hash example: https://repl.it/GTvi/2 (Thanks Eric!)
Private - Mode of Array answer with seven steps: https://github.com/kattak/first_interview_questions/blob/master/04_mode_of_array.rb
Slides: https://docs.google.com/presentation/d/1KsCcdjA9Ijj3c8ZpCeFZYkXQgG3Fnl1WQwlI__Pjqtg/edit?usp=sharing
Free Udemy course on Technical Interviewing: https://classroom.udacity.com/courses/ud513/lessons/7174469398/concepts/71213347930923#
Out of Office Hours: https://www.outofofficehours.com/
Code Buddies: https://codebuddies.org/

Feedback (from March 13, 2017)

Liked start and end time
Liked pairing
Like watching the video, but starting at 7pm would be better
Post resources in group

kattak/WWC Algorithms Workshop 03.13.2017.md