数据结构：哈希表（除留取余法--链地址法）

#include <iostream>
using namespace std;


//哈希函数的构造方法：除留取余法
//处理冲突机制：链地址法
typedef struct _NODE
{
  int key;
  struct _NODE* next;
}_NODE;

typedef struct Hash_Table
{
  _NODE* pChainHash[13];
}Hash_Table;

//初始化哈希表
Hash_Table* InitHashTable()
{
  Hash_Table* pHashTable = new Hash_Table;
  memset( pHashTable, 0, sizeof(Hash_Table) );
  return pHashTable;
}

//在哈希表中查找数据
_NODE* FindDataInHash( Hash_Table* pHashTable, int key )
{
  if ( !pHashTable )
    return NULL;
  _NODE* pNode = NULL;
  if ( !(pNode = pHashTable->pChainHash[ key % 13 ] ) )
    return NULL;
  while ( pNode )
  {
    if ( pNode->key == key )
      return pNode;
    pNode = pNode->next;
  }
  return NULL;
}

//在哈希表中插入数据
bool InsertDataToHash( Hash_Table* pHashTable, int key )
{
  if ( !pHashTable ) 
    return false;
  if ( NULL != FindDataInHash( pHashTable, key ) )
    return false;//数据已在里面
  
  _NODE* pNewNode = new _NODE;
  memset( pNewNode, 0, sizeof( _NODE ) );
  pNewNode->key = key;

  _NODE* pNode = NULL;
  pNode = pHashTable->pChainHash[ key % 13 ];
  if ( !pNode )
  {
    pHashTable->pChainHash[ key % 13 ] = pNewNode;
  }
  else
  {
    while( pNode->next )
    {
      pNode = pNode->next;
    }
    pNode->next = pNewNode;
  }
  return true;
}


//在哈希表中删除元素
bool DeleteDataInHash( Hash_Table* pHashTable, int key )
{
  if ( !pHashTable )
    return false;

  _NODE* pNode = NULL;
  if ( !( pNode = pHashTable->pChainHash[key % 13] ) )//无此数据
    return false;

  if ( pNode->key == key )//直接定址的数据
  {
    pHashTable->pChainHash[key % 13] = pNode->next;
    delete pNode;
    return true;
  }

  _NODE* pPreNode = pNode;//数据冲突，则在同一线性链表中查找
  pNode = pNode->next;
  while ( pNode )
  {
    if ( pNode->key == key )
    {
      pPreNode->next = pNode->next;
      delete pNode;
      return true;
    }
    pPreNode = pNode;
    pNode = pNode->next;
  }
  return false;
}