#include <iostream>
#include <iomanip>

struct dsdbl
{
    float x, y;
};

dsdbl ds_set(float a)
{
    dsdbl z;
    z.x = a;
    z.y = 0.0;
    return z;
}

dsdbl ds_mul(dsdbl dsa, dsdbl dsb)
{
    dsdbl dsc;
    float c11, c21, c2, e, t1, t2;
    float a1, a2, b1, b2, cona, conb, split = 8193.;

    cona = dsa.x * split;
    conb = dsb.x * split;
    a1 = cona - (cona - dsa.x);
    b1 = conb - (conb - dsb.x);
    a2 = dsa.x - a1;
    b2 = dsb.x - b1;

    c11 = dsa.x * dsb.x;
    c21 = a2 * b2 + (a2 * b1 + (a1 * b2 + (a1 * b1 - c11)));

    c2 = dsa.x * dsb.y + dsa.y * dsb.x;

    t1 = c11 + c2;
    e = t1 - c11;
    t2 = dsa.y * dsb.y + ((c2 - e) + (c11 - (t1 - e))) + c21;

    dsc.x = t1 + t2;
    dsc.y = t2 - (dsc.x - t1);

    return dsc;
}

dsdbl ds_add (dsdbl dsa, dsdbl dsb)
{
    dsdbl dsc;
    float t1, t2, e;

    t1 = dsa.x + dsb.x;
    e = t1 - dsa.x;
    t2 = ((dsb.x - e) + (dsa.x - (t1 - e))) + dsa.y + dsb.y;

    dsc.x = t1 + t2;
    dsc.y = t2 - (dsc.x - t1);
    return dsc;
}

dsdbl ds_sub(dsdbl dsa, dsdbl dsb)
{
    dsdbl dsc;
    float e, t1, t2;

    t1 = dsa.x - dsb.x;
    e = t1 - dsa.x;
    t2 = ((-dsb.x - e) + (dsa.x - (t1 - e))) + dsa.y - dsb.y;

    dsc.x = t1 + t2;
    dsc.y = t2 - (dsc.x - t1);
    return dsc;
}

float ds_compare(dsdbl dsa, dsdbl dsb)
{
    if (dsa.x < dsb.x) return -1.;
    else if (dsa.x == dsb.x)
    {
        if (dsa.y < dsb.y) return -1.;
        else if (dsa.y == dsb.y) return 0.;
        else return 1.;
    }
    else return 1.;
}

dsdbl double_to_ds(double d)
{
     float x = (float) d;
     float y = d - (double) x;
     return dsdbl { x, y };
}

int main()
{
    double x = 0.0194453596504303195813267990388339967467;
    double y = -1.7868687567166214869018858735216781497002;
    dsdbl a = double_to_ds(x);
    dsdbl b = double_to_ds(y);

    dsdbl ab = ds_mul(a, b);
    double xy = x * y;
    std::cout << std::fixed << std::setprecision(40) << x << std::endl;
    std::cout << std::fixed << std::setprecision(40) << y << std::endl;
    std::cout << std::fixed << std::setprecision(40) << xy << std::endl;
    std::cout << std::fixed << std::endl;
    std::cout << std::fixed << std::setprecision(40) << a.x << ' ' << a.y << std::endl;
    std::cout << std::fixed << std::setprecision(40) << b.x << ' ' << b.y << std::endl;
    std::cout << std::fixed << std::setprecision(40) << ab.x << ' ' << ab.y << std::endl;

    double abdbl = double(ab.x) + double(ab.y);
    std::cout << std::endl;
    std::cout << std::fixed << std::setprecision(40) << xy << std::endl;
    std::cout << std::fixed << std::setprecision(40) << abdbl << std::endl;

    dsdbl xyds = double_to_ds(xy);
    std::cout << ds_compare(xyds, ab) << std::endl;
}