#include<iostream>
using namespace std;

struct ListNode;
typedef struct ListNode *Position;
struct Hash_table;
typedef Hash_table *Hashtab;
typedef Position List;

#define Min_table_size 10

struct ListNode
{
int Emelent;
Position Next;
};

struct Hash_table
{
int Table_size;
List *Thelist;//指向鏈表的鏈表
};

//////////////相關函數聲明//////////////////////
Hashtab Inittable(int Table_size); //初始化一個散列
Position Find(int x, Hashtab H); //查找元素x,返回對應的位置
int Hash(int x); //散列函數
void Insert(int Key, Hashtab H); //在散列中插入元素Key
void Delete(int Key, Hashtab H); //在散列中刪除元素Key

///////////////相關函數定義////////////////////
Hashtab Inittable(int table_size)
{
Hashtab H;
if (table_size < Min_table_size)
{
cout << "Table size is too small" << endl;
return NULL;
}

H = (Hashtab)malloc(sizeof(Hash_table));
if (H == NULL) cout << "out of space" << endl;
H->Table_size = table_size;
H->Thelist = (List*)malloc(sizeof(Position) * H->Table_size);//不知道Position裏頭有多少個元素也可以分配內存嗎
if (H->Thelist == NULL) cout << "out of space" << endl;
for (int i = 0; i != H->Table_size; ++i)
{
H->Thelist[i] = (Position)malloc(sizeof(ListNode));
if (H->Thelist[i] == NULL) cout << "out of space" << endl;
else
{
H->Thelist[i]->Emelent = i;
H->Thelist[i]->Next = NULL;
}
}
return H;
}

int Hash(int x) //對10取余數
{
return x % 10;
}

Position Find(int x, Hashtab H)
{
Position P;
List L;

L = H->Thelist[Hash(x)]; //指向含有那個元素的表頭
P = L->Next;
while (P != NULL && P->Emelent != x)
P = P->Next;
return P;
}

void Insert(int Key, Hashtab H)
{
Position Pos, Newcell;
List L;
Pos = Find(Key, H); //先找找看，有沒有Key,有就算了
if (Pos == NULL)
{
Newcell = (Position)malloc(sizeof(ListNode));
if (Newcell == NULL) cout << "out of space" << endl;
else //插入到槽後面的第一個位置
{
L = H->Thelist[Hash(Key)];
Newcell->Next = L->Next;
Newcell->Emelent = Key;
L->Next = Newcell;
}
}
}

void Delete(int Key, Hashtab H)
{
Position p, Tmpcell;
List L;
p = Find(Key, H);
if (p == NULL)
cout << "not find the " << Key << endl;
else
{
L = H->Thelist[Hash(Key)];
p = L;
while (p->Next != NULL && p->Next->Emelent != Key) //尋找Key的前驅節點
{
p = p->Next;
}
//
Tmpcell = p->Next;
p->Next = Tmpcell->Next;
free(Tmpcell);
}

}
int main()
{
Hashtab H = Inittable(11);
cout << H->Thelist[9]->Emelent << endl;
Insert(1, H);
Insert(4, H);
Insert(9, H);
Insert(16, H);
Insert(25, H);
Insert(19, H);
Insert(29, H);
Delete(19, H);

cout << H->Thelist[9]->Next->Next->Emelent << endl;
return 0;
}

哈希，鏈接法解決沖突