1425  A simple problem
Time Limit : 1 Second
Memory Limit : 128 MB
Submission: 111
Solved: 31
 Description
xiaoY is crazy about determinant, One day he ask Mr HH a question “Mr HH, I have a hard computing problem on determinant, there is N point on 3D plane (all point is grid, which means coordinates are integer), and we define
Now the question is how many Det(pi,pj,pk) is Multiple of 3.” (i != j, j != k, k != i)
 Input
The first line is an integer T, means T cases followed:
Each case is described in the following way:
An integer N (N<=10000)
N lines followed, each line is an point xi yi zi(xi<2*10^9,yi<2*10^9,zi<2*10^9 )
 Output
For each case output the number of Det which is Multiple of 3.
 sample input

2 3 1 1 1 1 1 2 1 1 3 3 1 1 2 3 3 2 5 6 8
 sample output

Case #1: 6 Case #2: 0
 hint
Because answer may be too large, long long is recommended
 source