31122번 - 3D Geometry 스페셜 저지다국어

An axis-aligned tetrahedron (also known as triangular pyramid) $DABC$ is a convex polyhedron in three dimension with vertices

• $D: (x_1, y_1, z_1)$,
• $A: (x_2, y_1, z_1)$,
• $B: (x_1, y_2, z_1)$,
• $C: (x_1, y_1, z_2)$.

Also, an axis-aligned cube $PQRSDEFG$ is a convex polyhedron with vertices

• $P: (x_3, y_3, z_3)$,
• $Q: (x_3, y_3, z_4)$,
• $R: (x_3, y_4, z_3)$,
• $S: (x_3, y_4, z_4)$,
• $D: (x_4, y_3, z_3)$,
• $E: (x_4, y_3, z_4)$,
• $F: (x_4, y_4, z_3)$,
• $G: (x_4, y_4, z_4)$.

Given an axis-aligned tetrahedron $DABC$ and an axis-aligned cube $PQRSDEFG$, find the volume of their intersection.

The input consists of several test cases terminated by end-of-file. For each test case,

There are $4$ lines, and the $i$-th line contains three integers $x_i$, $y_i$, and $z_i$.

For each test case, output a float which denotes the volume.

Your answer is considered correct if its absolute or relative error doesn't exceed $10^{-6}$.

• $-500 \leq x_i, y_i, z_i \leq 500$ for each $1 \leq i \leq 4$
• $x_1 \neq x_2$, $y_1 \neq y_2$, $z_1 \neq z_2$
• $x_3 \neq x_4$, $y_3 \neq y_4$, $z_3 \neq z_4$
• In each input, the number of test cases does not exceed $10^5$.