Algorithm-and-Data-Structures/OpenAddressingHashTable/OpenAddressingHashTable.h at master · Peppe3009/Algorithm-and-Data-Structures · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
#include "OpenAddressingHashTable.cpp"

template <class T>
OpenAddressingHashTable<T>::OpenAddressingHashTable()
{
    this->size = 30;
    vector<pair<int, T>> tempV(this->size, make_pair(INF, T{}));
    this->hashtable = tempV;

}

template <class T>
OpenAddressingHashTable<T>::OpenAddressingHashTable(int m)
{
    this->size = m;
    vector<pair<int, T>> tempV(this->size, make_pair(INF, T{}));
    this->hashtable = tempV;
}

template <class T>
OpenAddressingHashTable<T>::OpenAddressingHashTable(vector<T> elements)
{
    this->size = 30;
    vector<pair<int, T>> tempV(this->size, make_pair(INF, T{}));
    this->hashtable = tempV;

    for (T element : elements)
    {
        this->insert(element);
    }
}

template <class T>
int OpenAddressingHashTable<T>::getSize()
{
    return this->size;
}

template <class T>
pair<int, T> OpenAddressingHashTable<T>::createKeyValuePair(T element)
{
    return make_pair(element, element);
}

template <>
pair<int, string> OpenAddressingHashTable<string>::createKeyValuePair(string element)
{

    return make_pair(element.size(), element);
}

template <class T>
int OpenAddressingHashTable<T>::doubleHashingFunction(int k, int i)
{
    int h_1 = k % this->size;
    int h_2 = 1 + (k % (this->size - 1));
    return (h_1 + i * h_2) % this->size;
}

template <class T>
void OpenAddressingHashTable<T>::insert(T element)
{
    pair<int, T> KeyValuePair = this->createKeyValuePair(element);
    int i = 0;
    while (i < this->size)
    {
        int q = this->doubleHashingFunction(KeyValuePair.first, i);
        if (this->hashtable.at(q).first == INF)
        {
            this->hashtable.at(q) = KeyValuePair;
            return;
        }
        else
        {
            i++;
        }
    }
    cerr << "Hash Table overflow" << endl;
    return;
}

template <class T>
bool OpenAddressingHashTable<T>::find(T element)
{
    pair<int, T> KeyValuePair = this->createKeyValuePair(element);
    int i = 0;
    int q = this->doubleHashingFunction(KeyValuePair.first, i);
    while (this->hashtable.at(q).first != INF || i != this->size)
    {
        q = this->doubleHashingFunction(KeyValuePair.first, i);
        if (this->hashtable.at(q) == KeyValuePair)
        {
            cout << "Element found at index: " << q << endl;
            return true;
        }
        else
        {
            i++;
        }
    }
    cout << "Element not found" << endl;
    return false;
}

template <class T>
void OpenAddressingHashTable<T>::remove(T element)
{
    if (this->find(element))
    {
        pair<int, T> KeyValuePair = this->createKeyValuePair(element);
        int i = 0;
        int q = this->doubleHashingFunction(KeyValuePair.first, i);
        while (this->hashtable.at(q).first != INF || i != this->size)
        {
            q = this->doubleHashingFunction(KeyValuePair.first, i);
            if (this->hashtable.at(q) == KeyValuePair)
            {
                pair<int, T> deletedPair (INF, T{});
                this->hashtable.at(q) = deletedPair;
                cout << "Element deleted at index: " << q << endl;
                return;

            }
            else
            {
                i++;
            }
        }
        return;
    }
    return;
}

template <class T>
void OpenAddressingHashTable<T>::remove(vector<T> elements)
{
    for (T element: elements)
    {
        this->remove(element);
    }
}


template <class T>
void OpenAddressingHashTable<T>::show()
{
    for (int i = 0; i < this->hashtable.size(); i++)
    {
        cout << i << ": " << this->hashtable.at(i).second << endl;
    }
}