#pragma once
#include <cmath>

struct double3 {
    double data[3];
    double3() {}
    double3(const double x, const double y, const double z)
    {
        data[0] = x;
        data[1] = y;
        data[2] = z;
    }
    double& operator[](int i) {return data[i];}
    const double operator[](int i) const {return data[i];}
    double3& operator=(const double3& a)
    {
        data[0] = a.data[0];
        data[1] = a.data[1];
        data[2] = a.data[2];
        return *this;
    }
    double3& operator+=(const double3& a)
    {
        data[0] += a.data[0];
        data[1] += a.data[1];
        data[2] += a.data[2];
        return *this;
    }
    double3& operator-=(const double3& a)
    {
        data[0] -= a.data[0];
        data[1] -= a.data[1];
        data[2] -= a.data[2];
        return *this;
    }
    double3& operator/=(const double& c)
    {
        data[0] /= c;
        data[1] /= c;
        data[2] /= c;
        return *this;
    }
    double norm2() const
    {
        return data[0]*data[0]+data[1]*data[1]+data[2]*data[2];
    }
    double norm() const
    {
        return sqrt(data[0]*data[0]+data[1]*data[1]+data[2]*data[2]);
    }
    operator double*() {return data;}
};

inline double3 operator*(const double& c, const double3& a)
{
    return double3(a.data[0]*c, a.data[1]*c, a.data[2]*c);
}

inline double3 operator*(const double3& a, const double& c)
{
    return double3(a.data[0]*c, a.data[1]*c, a.data[2]*c);
}

inline double operator*(const double3& a, const double3& b)
{
    return a.data[0]*b.data[0]+a.data[1]*b.data[1]+a.data[2]*b.data[2];
}

inline double3 operator/(const double3& a, const double& c)
{
    return double3(a.data[0]/c, a.data[1]/c, a.data[2]/c);
}

inline double3 operator+(const double3& a, const double3& b)
{
    return double3(a.data[0]+b.data[0], a.data[1]+b.data[1], a.data[2]+b.data[2]);
}

inline double3 operator-(const double3& a, const double3& b)
{
    return double3(a.data[0]-b.data[0], a.data[1]-b.data[1], a.data[2]-b.data[2]);
}