NxBigInt 클래스 구현

프로그램은 크게 외부에서 연산자 오버로딩을 이용하여 편하게 이용할 수 있는 함수들과 내부 함수부(실제 연산이 이루어지는 부분들)로 나뉘어져있습니다.

연산자 오버로딩을 처리하는 쪽 함수들은 모두 내부함수를 호출하기 때문에 별로 크게 설명할 내용이 없습니다.

#include "NxBigInt.h"

#include <stdio.h>
#include <memory.h>

#define ALLOCSIZE   4

const NxBigInt NxBigInt::Zero = 0;
const NxBigInt NxBigInt::One = 1;
const NxBigInt NxBigInt::Undefined;

NxBigInt::NxBigInt(int value)
{
    if( value < 0 ) { m_bNegative = true; value = -value; } else { m_bNegative = false; }
    m_nLen = 1;
    m_nSize = ALLOCSIZE;
    m_pnData = new uint32_t[m_nSize];
    m_pnData[0] = value;
}

NxBigInt::NxBigInt(const NxBigInt &value)
{
    m_bNegative = value.m_bNegative;
    m_nLen = value.m_nLen;
    m_nSize = value.m_nSize;
    m_pnData = new uint32_t[m_nSize];
    memcpy(m_pnData, value.m_pnData, m_nLen*sizeof(uint32_t));
}

NxBigInt::NxBigInt(const char *value)
{
    m_nLen = 1;
    m_nSize = ALLOCSIZE;
    m_pnData = new uint32_t[m_nSize];
    ConvertFromString(value);
}

NxBigInt::NxBigInt(const wchar_t *value)
{
    m_nLen = 1;
    m_nSize = ALLOCSIZE;
    m_pnData = new uint32_t[m_nSize];
    ConvertFromString(value);
}

NxBigInt::~NxBigInt()
{
    if( m_pnData != 0 )
    {
        delete[] m_pnData;
    }
}

NxBigInt NxBigInt::operator+(int value) const
{
    NxBigInt out(*this);
    out.AddTo(value);

    return out;
}

NxBigInt NxBigInt::operator+(const NxBigInt &value) const
{
    NxBigInt out(*this);
    out.AddTo(value);

    return out;
}

NxBigInt operator+(int first, const NxBigInt &second)
{
    return second + first;
}

NxBigInt NxBigInt::operator-() const
{
    NxBigInt out(*this);
    out.m_bNegative = ~out.m_bNegative;

    return out;
}

NxBigInt NxBigInt::operator-(int value) const
{
    NxBigInt out(*this);
    out.SubtractTo(value);
    
    return out;
}

NxBigInt NxBigInt::operator-(const NxBigInt &value) const
{
    NxBigInt out(*this);
    out.SubtractTo(value);

    return out;
}

NxBigInt operator-(int first, const NxBigInt &second)
{
    NxBigInt out(first);
    out.SubtractTo(second);

    return out;
}

NxBigInt NxBigInt::operator*(int value) const
{
    NxBigInt out(*this);
    out.MultiplyTo(value);

    return out;
}

NxBigInt NxBigInt::operator*(const NxBigInt &value) const
{
    NxBigInt out(*this);
    out.MultiplyTo(value);

    return out;
}

NxBigInt operator*(int first, const NxBigInt &second)
{
    return second * first;
}

NxBigInt NxBigInt::operator/(int value) const
{
    NxBigInt out(*this);
    out.DivideTo(value);

    return out;
}

NxBigInt NxBigInt::operator/(const NxBigInt &value) const
{
    NxBigInt out(*this);
    out.DivideTo(value);

    return out;
}

NxBigInt NxBigInt::operator%(int value) const
{
    NxBigInt out(*this);
    out.ModulaTo(value);

    return out;
}

NxBigInt NxBigInt::operator<<(int value) const
{
    NxBigInt out = *this;
    out.ShiftToLeft(value);

    return out;
}

NxBigInt NxBigInt::operator>>(int value) const
{
    NxBigInt out = *this;
    out.ShiftToRight(value);

    return out;
}

NxBigInt &NxBigInt::operator=(int value)
{
    if( value < 0 ) { m_bNegative = true; value = -value; } else { m_bNegative = false; }
    m_nLen = 1;
    m_pnData[0] = value;
    return *this;
}

NxBigInt &NxBigInt::operator=(int64_t value)
{
    if( value < 0 ) { m_bNegative = true; value = -value; } else { m_bNegative = false; }
    m_nLen = 2;
    m_pnData[0] = value & 0xffffffff;
    m_pnData[1] = value >> 32;
    return *this;
}

NxBigInt &NxBigInt::operator=(const char *value)
{
    ConvertFromString(value);
    return *this;
}

NxBigInt &NxBigInt::operator=(const wchar_t *value)
{
    ConvertFromString(value);
    return *this;
}

NxBigInt &NxBigInt::operator+=(int value)
{
    AddTo(value);

    return *this;
}

NxBigInt &NxBigInt::operator+=(const NxBigInt &value)
{
    AddTo(value);

    return *this;
}

NxBigInt &NxBigInt::operator*=(int value)
{
    MultiplyTo(value);

    return *this;
}

NxBigInt &NxBigInt::operator*=(const NxBigInt &value)
{
    MultiplyTo(value);

    return *this;
}

NxBigInt &NxBigInt::operator/=(int value)
{
    DivideTo(value);

    return *this;
}

NxBigInt &NxBigInt::operator/=(const NxBigInt &value)
{
    DivideTo(value);

    return *this;
}

NxBigInt &NxBigInt::operator%=(int value)
{
    DivideTo(value);

    return *this;
}

NxBigInt &NxBigInt::operator<<=(int value)
{
    ShiftToLeft(value);

    return *this;
}

NxBigInt &NxBigInt::operator>>=(int value)
{
    ShiftToRight(value);

    return *this;
}

NxBigInt::operator bool() const
{
    return !(m_nLen <= 1 && m_pnData[0] == 0);
}

std::ostream &operator <<(std::ostream &output, const NxBigInt &number)
{
    char buf[2048];

    number.ConvertToString(buf, 2048);
    
    output << buf;

    return output;
}