hash.cpp

读取Segy格式地震数据的类SegyReader, 在segy.h文件中有segy卷头/道头的每一个字段的中文详细说明,方便大家查询使用. 另外, 使用QT3.x制作的GUI界面程序, 可

#include "hash.h"

CHash::CHash(int iSlots) 
{
    if (iSlots < 5) iSlots = 5;
    m_pHashSlots = new CHashElem*[iSlots];
    for(int i=0;i<iSlots;i++)
        m_pHashSlots[i]=0;
    m_iNumSlots = iSlots;
    m_iLength=0;
}


CHash::~CHash() 
{
    if (m_pHashSlots)
    {
        CHashElem *phe;
        for (int i=0;i<m_iNumSlots;i++) 
        {
            phe = m_pHashSlots[i];
            while (phe != 0) 
            {
                CHashElem *pNext = phe->pNext;
                delete phe;
                phe = pNext;
            }
        }
        delete m_pHashSlots;
        m_pHashSlots = 0;
    }
}


bool CHash::QueryValue(const int Key,int& Val) 
{
    bool bRet=false;
    unsigned int num=(unsigned int)Key%m_iNumSlots;    
    if (num >= 0)
    {
        CHashElem *pElem = m_pHashSlots[num];
        while (pElem) 
        {
            if (pElem->Key==Key) 
            {
                Val=pElem->Val;
                bRet=true;
            }
            pElem = pElem->pNext;
        }

    }
    return bRet;

}
CHashElem*  CHash::QueryElem(const int iIndex)
{
    CHashElem *pElem=0;
    int iSlot=0;
    pElem=m_pHashSlots[0];
    for(int i=0;i<=iIndex;i++)
    {
BEGIN:
        if(iSlot<m_iNumSlots)
        {            
            if(!pElem)
            {
                iSlot++;
                pElem=m_pHashSlots[iSlot];
                goto BEGIN;
            }
            else
            {
                pElem=pElem->pNext;

            }
        }
        else
        {
            pElem=0;
            break;
        }

    }
    return pElem;

}

bool CHash::Insert(int Key, int Val) 
{
    bool bRet=false;
    unsigned int num=(unsigned int)Key%m_iNumSlots;    
    if (num >= 0)
    {
        if (m_pHashSlots[num]) 
        {
            CHashElem *pIns = m_pHashSlots[num];
            while (pIns->pNext) 
            {
                pIns = pIns->pNext;
            }
            pIns->pNext = new CHashElem;
            pIns->pNext->pNext = 0;
            pIns->pNext->Val = Val;
            pIns->pNext->Key = Key;
            bRet=true;
            m_iLength++;
        } 
        else 
        {
            m_pHashSlots[num] = new CHashElem;
            m_pHashSlots[num]->pNext = 0;
            m_pHashSlots[num]->Key = Key;
            m_pHashSlots[num]->Val = Val;
            bRet=true;
            m_iLength++;
        }
    }
    return bRet;
}



bool CHash::Remove(const int Key) 
{
    bool bRet=false;
    unsigned int num=(unsigned int)Key%m_iNumSlots;    
    if (num >= 0) 
    {
        CHashElem *pElem = m_pHashSlots[num];
        CHashElem *pPrev = 0;
        while (pElem) 
        {
            if (pElem->Key==Key) 
            {
                if (pPrev) 
                {
                    pPrev->pNext = pElem->pNext;
                }
                else 
                {
                    m_pHashSlots[num] = pElem->pNext;
                }
                delete pElem;
                bRet=true;
                m_iLength--;
                break;
            }
            pPrev = pElem;
            pElem = pElem->pNext;
        }
    }
    return bRet;
}
int CHash::GetLength()
{
    return m_iLength;
}
int CHash::GetSlotNum()
{
    return m_iNumSlots;
}