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eprecomp.h

#ifndef CRYPTOPP_EPRECOMP_H
#define CRYPTOPP_EPRECOMP_H

#include "integer.h"
#include "algebra.h"
#include <vector>

NAMESPACE_BEGIN(CryptoPP)

template <class T> class ExponentiationPrecomputation
{
public:
        typedef T Element;
        typedef AbstractGroup<T> Group;

        ExponentiationPrecomputation() : m_group(NULL) {}

        void SetGroupAndBase(const Group &group, const Element &base);
        void Precompute(unsigned int maxExpBits, unsigned int storage);
        void PrepareCascade(std::vector<BaseAndExponent<Element> > &eb, const Integer &exponent) const;
        Element Exponentiate(const Integer &exponent) const;
        Element CascadeExponentiate(const Integer &exponent, const ExponentiationPrecomputation<T> &pc2, const Integer &exponent2) const;

        const Group *m_group;
        unsigned int m_windowSize;
        Integer m_exponentBase;                 // what base to represent the exponent in
        std::vector<Element> m_bases;   // precalculated bases
};

NAMESPACE_END

#endif

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