0 [4, 10, 10, 8]
0 3
0 1
1 [4, 10, 10, 8]
1 2
1 0
2 [4, 10, 10, 8]
2 3
2 1
3 [4, 10, 10, 8]
3 2
0 [4, 3, 8]
0 2
0 1
1 [4, 3, 8]
1 2
1 0
2 [4, 3, 8]
2 3