hash table(用乘法散列法实现）

hash table(用乘法散列法实现）

#ifndef C11LEARN_HASHMULTI_H
#define C11LEARN_HASHMULTI_H
#include "HashDivision.h"
template<typename T>
class HashMulti:public HashDivision<T>
{
private:
    long w;
    long p;
    long long s;
    long long two_32;
public:
    HashMulti():HashDivision<T>(1<<14){
        s = 2654435769;
        w = 32;
        p = 14;
        two_32 = 1;
        two_32 = two_32<<32;
    }
    HashMulti(const HashMulti<T>& multi):HashDivision<T>(1<<14){
        s = 2654435769;
        w = 32;
        p = 14;
        two_32 = 1;
        two_32 = two_32<<32;
        HashDivision<T>::copy(multi);
    }

protected:
    virtual int hashing(int key);
};
template<typename T>
int HashMulti<T>::hashing(int key){
    return ((key*s)%two_32)>>(w-p);
}
#endif //C11LEARN_HASHMULTI_H

测试代码

    HashMulti<string> hashMulti;
    hashMulti[2] = "hello";
    hashMulti[123456] = "world";
    cout << hashMulti[2] << endl;
    cout << hashMulti[123456] << endl;

辅助类
HashDivision链接地址

乘法哈希和除法哈希的不同点是哈希函数不同，
共同点都是用双向链表解决冲突问题。