## COVER2 - 3D Cover

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In the 3D Cartesian coordinate system, there are n cubes.These cubes are all axis-paralleled. What's the volume of the union of these cubes?

### Input

There is a single integer m in the very first line of the input, the number of test cases. m blocks follow.

For each test, the first line contains a single integer n(1<=n<=100), the number of cubes. n lines follow, each contains four integers x,y,z,r(-1000<=x,y,z<=1000,1<=r<=200), separated by spaces. x,y,z are the X,Y,Z coordinates of the center of the cube, and r is the distance between the center and any surface of the cube.

### Output

m lines,each contains a single integer - the answer.

### Example

```Sample Input:
1
3
0 0 0 3
1 -1 0 1
19 3 5 6
Sample Output:
1944
```

 Added by: Fudan University Problem Setters Date: 2007-04-01 Time limit: 1s Source limit: 50000B Memory limit: 1536MB Cluster: Cube (Intel G860) Languages: All except: C99 ERL JS-RHINO Resource: Chinese National Olympiad in Informatics 1997,Day 2; description by Blue Mary