/****************************************************************************
 *
 * Copyright (c) 2000, 2001 
 *     Machine Group
 *     Software Research Lab.
 *     Institute of Computing Tech.
 *     Chinese Academy of Sciences
 *     All rights reserved.
 *
 * This file is the confidential and proprietary property of 
 * Institute of Computing Tech. and the posession or use of this file requires 
 * a written license from the author.
 * Filename: ContextStat.h
 * Abstract:
 *           
 *             interface for the CContextStat class.
 * Author:   Kevin Zhang 
 *          (zhanghp@software.ict.ac.cn)
 * Date:     2002-1-24
 *
 * Notes:
 *                
 * 
 ****************************************************************************/

#if !defined(AFX_CONTEXTSTAT_H__DA515FDC_F8F9_48F6_B25D_D2B91011528B__INCLUDED_)
#define AFX_CONTEXTSTAT_H__DA515FDC_F8F9_48F6_B25D_D2B91011528B__INCLUDED_

#if _MSC_VER > 1000
#pragma once
#endif // _MSC_VER > 1000
struct tagContext{
    int nKey;//The key word
    int **aContextArray;//The context array
    int *aTagFreq;//The total number a tag appears
    int nTotalFreq;//The total number of all the tags
    struct tagContext *next;//The chain pointer to next Context
};
typedef struct tagContext MYCONTEXT,*PMYCONTEXT;
class CContextStat  
{
public:
    bool SetTableLen(int nTableLe);
    int GetFrequency(int nKey,int nSymbol);
    double GetContextPossibility(int nKey,int nPrev,int nCur);
    bool Load(char *sFilename);
    bool Save(char *sFilename);
    bool Add(int nKey,int nPrevSymbol,int nCurrentSymbol,int nFrequency);
    bool SetSymbol(int *nSymbol);
    CContextStat();
    virtual ~CContextStat();
private:
    int m_nTableLen;
    int *m_pSymbolTable;
    PMYCONTEXT m_pContext;
    int m_nCategory;
protected:
    bool GetItem(int nKey,PMYCONTEXT *pItemRet);
};

#endif // !defined(AFX_CONTEXTSTAT_H__DA515FDC_F8F9_48F6_B25D_D2B91011528B__INCLUDED_)