Algorithms For Dummies

 

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Chaining: Each slot in the hash table can hold multiple values. You can 

implement this approach by using a list within a list. Every time a collision 

occurs, the code simply appends the value to the list in the target slot. This 

approach offers the benefit of knowing that the hash will always produce the 

correct slot, but the list within that slot will still require some sort of sequential 

(or other) search to find the specific value.

Creating your own hash function

You may at times need to create custom hash functions in order to meet the needs 

of the algorithm you use or to improve its performance. Apart from cryptographic 

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CHAPTER 7

  Arranging and Searching Data 

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uses (which deserve a book alone), Chapter 12 presents common algorithms that 

leverage different hash functions, such as the Bloom Filter, the HyperLogLog, and 

the  Count-Min Sketch, that leverage the properties of custom hash functions to 

extract information from huge amounts of data.

You can find many examples of different hash functions in the Python 

hashlib

 

package. The 

hashlib

 package contains algorithms such as these: