Limitless Matrix

The i^th row consists of M_i,1, M_i,2, M_i,3, M_i,4 and M_i,5.
The jth column consists of M_1,j , M_2,j , M_3,j , M_4,j and M_5,j .
The main diagonal line consists of M_1,1, M_2,2, M_3,3, M_4,4 and M5_,5.
The sub diagonal line consists of M_1,5, M_2,4, M_3,3, M_4,2 and M_5,1.
However, Mr.Frog will go to Hong Kong today. He asks you for help.

The first line contains an integer T, where T is the number of test cases. T test cases follow.

For each test case, the only line contains two integers N and K.

1<=T<=10

1<=N<=10³

-10⁹<=K<=10⁹

For each test case, output one line containing “Case #x:”, where x is the test case number (starting from
1). If there is no solution, print “IMPOSSIBLE” in the next line; otherwise, print N lines with N integers.
If there are many multiple optimal answers, output any one of them.

2
5 -7
3 373248

Case #1:
IMPOSSIBLE
Case #2:
36 108 96
192 72 27
54 48 144