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{Dictionary Word Finder}

The Question

Given

1. An alphabetical array of dictionary entries and
2. A word to search for

 

find and return that word's definition (if it exists).

 

This array of dictionary entries will be formatted like so:

Example

insert 'a'

[ 'a' ]

What do you notice about the entires?

Naive Approach

(aka Brute Force)

insert 'a'

[ 'a' ]

• What is the bigO time complexity?
• Space complexity?
• Nice way to es6-ify this?

es6 Array.prototype.find()

 

insert 'a'

[ 'a' ]

• What is the bigO time complexity?
• Space complexity?
• Nice way to es6-ify this?

Optimized approach

insert 'a'

[ 'a' ]

What have we not taken full advantage of yet? 

Optimized approach

Binary search

insert 'a'

[ 'a' ]

What next?

Optimized approach

Binary search

insert 'a'

[ 'a' ]

Optimized approach

Binary search

insert 'a'

[ 'a' ]

What is the time and space complexity?

Interviewer Tips

 

insert 'a'

[ 'a' ]

1. Meet the interviewee where she is at.
2. If time permits, try to help her optimize by asking her what piece of info has not been made use of.
3. If that doesn't lead her to BS, ask her how SHE would look for a word in a dictionary.
4. If time permits, try to lead her to pseudo-coding out a BS approach, then maybe coding it.
5. If your interviewee goes down a rabbit-hole trying to implement a compareByAlphabeticalOrder function, just let her know that she can use '<'  and '>' to compare strings.
6. Please keep track of time, we will reconvene here at 10:15 and discuss the EVEN MORE optimized approach. 😯😮😲😀😎

 

 

 

Further Optimized approach

Hash maps

insert 'a'

[ 'a' ]

What is the time and space complexity?

 

 

Takeaways?

 

insert 'a'

[ 'a' ]

Takeaways?

 

insert 'a'

[ 'a' ]

What else did you learn from this problem?

What questions do you have?