hash_map.py

# Program to create hash table from scratch
# We can create hash functions in different ways

class hashmap:
    def __init__(self, size):
        self.size = size
        self.map = [None] * self.size

    def get_hash(self, key):
        sum = 0
        for i in key:
            sum += ord(i)
        return sum % self.size

    def add(self, key, value):
        index = self.get_hash(key)
        if self.map[index] == None:
            self.map[index] = list([key, value])
        else:
            for pair in self.map[index]:
                    print(pair)
            self.map[index].append([key, value])

    def get_value(self, key):
        index = self.get_hash(key)
        if self.map[index] == None:
            print('Key error')
        else:
            for pair in self.map[index]:
                if pair != None:
                    if pair[0] == key:
                        return pair

    def delete(self, key):
        index = self.get_hash(key)
        if self.map[index] == None:
            print('key error')
        else:
            self.map[index] = None

    def print_hashmap(self):
        print(self.map)

if __name__ == '__main__':
    h = hashmap(6)
    h.add('sourav kumar', 100)
    h.add('elon musk', 95)
    h.add('jennifer lawrence', 98)
    #h.add('sourav kumar', 120)
    h.print_hashmap()


# some of the important hash functions are shown below

# def getHash(self, key):
#     index, p = 0, 1
#     for i in range(len(key)):
#         index = index + (ord(key[i]) * p) % self.size
#         index = index % self.size
#         p = (p * 37) % self.size
#
#     return index