Charlotte - Space

[charlottea13]

Hash Table Practice

Congratulations! You're submitting your assignment!

Comprehension Questions

Question	Answer
Why is a good Hash Function Important?	they are fast - 0(1) time complexity for insert/delete/lookup, to avoid collisions as the load factor increases
How can you judge if a hash function is good or not?	1. fast 2. values are evenly distributed throughout 3. the hashing is random 4. keys are close - values spread out.
Is there a perfect hash function? If so what is it?	yes. it's one-to-one mapping ie: a person to a unique id
Describe a strategy to handle collisions in a hash table	quadratic probing - looks at indexes away from the current probing position - say 5 indexes and then 20 indexes and so on.
Describe a situation where a hash table wouldn't be as useful as a binary search tree	when there are duplicate keys
What is one thing that is more clear to you on hash tables now	if you can use this data structure - you should - b/c of the time complexity

[CheezItMan]

Nice work Charlotte, you hit most of the learning goals with just 1 test failing. You also need to take a look at time complexity a bit. This is something to work on here.

[CheezItMan]

👍 , however your time complexity is off. You loop through all the strings so it's a minimum of O(n). If you assume the strings are all small then the sorting can be ignored.

[CheezItMan]

This is most of the solution, the only weakness is that the sort_by you're doing doesn't preserve the order the elements were encountered in. You also have the time complexity wrong because you have a loop through all the elements and you're sorting them.