HDU 1411 Anniversary Mystery Building (Euler tetrahedron formula)

HDU 1411:http://acm.hdu.edu.cn/showproblem.php?pid=1411

The person is one of you a hexahedral six sides, seek hexahedral volume.

Train of thought: there is no idea, is to use Euler tetrahedron formula directly into.

Euler Tetrahedron formula:

There are a lot of specific derivation online.  eg. http://blog.csdn.net/archibaldyangfan/article/details/8035332

More Wonderful content: http://www.bianceng.cnhttp://www.bianceng.cn/Programming/sjjg/

void Solve ()
{
    Double A, B, C, M, N, l;
    scanf ("%lf%lf%lf%lf%lf%lf", &a, &c, &b, &n, &l, &m);
    Double V = (double) sqrt (4.0*a*a*b*b*c*c-a*a* (b*b+c*c-m*m) * (b*b+c*c-m*m)-
                             b*b* (c*c+a*a-n*n) * (c*c+a*a-n*n)-c*c * (a*a+b*b-l*l) *
                             (A*A+B*B-L*L) + (a*a+b*b-l*l) * (b*b+c*c-m*m) * (c*c+a*a-n*n))/12.0;
    printf ("%.4lf\n", V);
}
  
HDU 1411