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hash_table.py
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hash_table.py
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class HashTable:
def __init__(self, capacity):
if not isinstance(capacity, int):
capacity = int(capacity)
self.capacity = capacity
self.table = [None] * capacity
@staticmethod
def hash_code(string: str):
string = str(string) # ensure input is cast to str for hash coding
hc = 0 # what we'll return
for character in string: # create hash code incrementally for each char in the str
hc = 31 * hc + ord(character) # 31 is used because it is a prime number
return hc
def add(self, key, value):
hc = HashTable.hash_code(key)
bucket = hc % self.capacity
if self.table[bucket] is None:
self.table[bucket] = [(key, value)]
else:
self.table[bucket].append((key, value))
def get(self, key):
hc = HashTable.hash_code(key)
bucket = hc % self.capacity
if self.table[bucket] is not None:
for (K, V) in self.table[bucket]:
if K == key:
return V
return None # if key not found, return None