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Overloading "less than" operator

LadyInRed (10)
Hi,

I this problem i try to overload the "less than" operator in three ways :

bool operator < (const Box& aBox) const;
bool operator < (const double aValue) const;
bool operator < (const double aValue, const Box& aBox);

but i receive an error :
"error : 'bool Box::operator < (const double aValue, const Box& aBox)' must take exactly one argument"

What i supossed to do ? 

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#include <iostream>
#include <cstdlib>
#include <ctime>

using namespace std;

class Box
{
public:
    Box(double aLength = 1.0, double aWidth = 1.0, double aHeight = 1.0);
    double volume() const;
    double getLength() const;
    double getWidth() const;
    double getHeight() const;
    bool operator < (const Box& aBox) const;
    bool operator < (const double aValue) const;
    bool operator < (const double aValue, const Box& aBox)
private:
    double length;
    double width;
    double height;
};

Box::Box(double aLength, double aWidth, double aHeight)
{
    length = aLength;
    width = aWidth;
    height = aHeight;
}

double Box::volume() const
{
    return (length*width*height);
}

double Box::getLength() const
{
    return length;
}

double Box::getWidth() const
{
    return width;
}

double Box::getHeight() const
{
    return height;
}

bool Box::operator < (const Box& aBox) const
{
    return this->volume() < aBox.volume();
}

bool Box::operator < (const double aValue) const
{
    return this->volume() < aValue;
}

bool Box::operator < (const double aValue, const Box& aBox)
{
    return aValue < aBox.volume();
}

inline int random(int count)
{
    return 1+static_cast<int>(count*static_cast<double>(rand()) / (RAND_MAX+1.0));
}

void show(const Box& aBox)
{
    cout <<endl << aBox.getLength() << " by " << aBox.getWidth() << " by " << aBox.getLength();
}

int main()
{
    const int dimLimit = 100;
    srand((unsigned)time(0));
    const int boxCount = 20;
    Box boxes[boxCount];
    for(int i=0; i<boxCount; i++)
        boxes[i] = Box(random(dimLimit), random(dimLimit), random(dimLimit));

    Box *pLargest = &boxes[0];

    for(int i=1; i<boxCount; i++)
        if(*pLargest < boxes[i])
            pLargest = &boxes[i];
    cout << "\n The largest box in the array has dimensions : ";
    show(*pLargest);

    int volMin = 100000.0;
    int volMax = 500000.0;
    cout <<endl << " Box with volumes between " << volMin << " and " << volMax << " are : ";
    for(int i=0; i<boxCount; i++)
        if(volMin < boxes[i] && boxes[i] < volMax)
            show(boxes[i]);
    return 0;
}
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