Implementing hash tables

To implement the hash table, we start by creating a class to hold hash table items. These need to have a key and a value since the hash table is a {key-value} store:

class HashItem: 
    def __init__(self, key, value): 
        self.key = key 
        self.value = value 

Next, we start working on the hash table class itself. As usual, we start with a constructor:

class HashTable: 
     def __init__(self): 
         self.size = 256 
         self.slots = [None for i in range(self.size)] 
         self.count = 0 

Standard Python lists can be used to store data elements in a hash table. Let’s set the size of the hash table to 256 elements to start with. Later, we will look at strategies for how to grow the hash table as we begin filling it up. We will now initialize a list containing 256 elements in the code. These are the positions where the elements are to be stored—the slots or buckets. So, we have 256 slots to store elements...