2 4 -1 -2
-3 7 -1 4
5 -9 2 7
2 -5 1 2
2 4 -1 -2
-3 7 -1 4
5 -9 2 7
2 -5 1 2
-1 4 2 -2 -1 4 2 -2 -1 4 2 -2 -1 4 2 -2 -1 4 2 -2
-1 7 -3 4 = 0 3 -5 8 = 0 1 9 3 = 0 1 9 3 = 0 1 9 3 = -83 不知对不对,我是经常算错
2 -9 5 7 0 1 9 3 0 -1 4 0 0 0 13 3 0 0 13 3
1 -5 2 2 0 -1 4 0 0 3 -5 8 0 0 -32 -1 0 0 0 83/13