Chaining Hash table

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#include <iostream>#include <Windows.h>#include <vector>using namespace std;const int TABLE_SIZE = 51;template <typename T>class LinkedHashEntry {private:int key;T value;LinkedHashEntry<T> *next;public:LinkedHashEntry(int key, int value) {this->key = key;this->value = value;this->next = NULL;}int getKey() {return key;}T getValue() {return value;}void setValue(const T &value) {this->value = value;}LinkedHashEntry *getNext() {return next;}void setNext(LinkedHashEntry<T> *next) {this->next = next;}};template <typename T>class HashMap {private:LinkedHashEntry<T> **table;public:HashMap() {table = new LinkedHashEntry<T>*[TABLE_SIZE];for (int i = 0; i < TABLE_SIZE; i++)table[i] = NULL;}T get(int key) {int hash = (key % TABLE_SIZE);if (table[hash] == NULL)return -1;else {LinkedHashEntry<T> *entry = table[hash];while (entry != NULL && entry->getKey() != key)entry = entry->getNext();if (entry == NULL)return -1;elsereturn entry->getValue();}}void put(int key, const T &value) {int hash = (key % TABLE_SIZE);if (table[hash] == NULL)table[hash] = new LinkedHashEntry<T>(key, value);else {LinkedHashEntry<T> *entry = table[hash];while (entry->getNext() != NULL && entry->getKey() != key)entry = entry->getNext();// exist entity with the same key value, so replace// no same key value, insertif (entry->getKey() == key)entry->setValue(value);elseentry->setNext(new LinkedHashEntry<T>(key, value));}}void remove(int key) {int hash = (key % TABLE_SIZE);if (table[hash] != NULL) {LinkedHashEntry<T> *prevEntry = NULL;LinkedHashEntry<T> *entry = table[hash];while (entry->getNext() != NULL && entry->getKey() != key) {prevEntry = entry;entry = entry->getNext();}if (entry->getKey() == key) {if (prevEntry == NULL) {LinkedHashEntry<T> *nextEntry = entry->getNext();delete entry;table[hash] = nextEntry;}else {LinkedHashEntry<T> *next = entry->getNext();delete entry;prevEntry->setNext(next);}}}}~HashMap() {for (int i = 0; i < TABLE_SIZE; i++)if (table[i] != NULL) {LinkedHashEntry<T> *prevEntry = NULL;LinkedHashEntry<T> *entry = table[i];while (entry != NULL) {prevEntry = entry;entry = entry->getNext();delete prevEntry;}}delete[] table;}};int main(){HashMap<int> hashtable;hashtable.put(10, 100);hashtable.put(61, 199);hashtable.put(1, 10);hashtable.put(52, 22);cout << hashtable.get(1) << endl;hashtable.put(1, 1001);cout << hashtable.get(1) << endl;hashtable.remove(1);cout << hashtable.get(1) << endl;system("PAUSE");return 0;}

The code is from:

http://www.algolist.net/Data_structures/Hash_table/Chaining

The top of chaining hash table is:

keys)

More proof and detail could be found at:

http://staff.ustc.edu.cn/~csli/graduate/algorithms/book6/chap12.htm

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