0 [4, 3, 9, 1, 1]
0 4
0 1
1 [4, 3, 9, 1, 1]
1 2
1 0
2 [4, 3, 9, 1, 1]
2 3
2 1
3 [4, 3, 9, 1, 1]
3 4
3 2
4 [4, 3, 9, 1, 1]
4 3
0 [4, 3, 9, 7]
0 3
0 1
1 [4, 3, 9, 7]
1 2
1 0
2 [4, 3, 9, 7]
2 3
2 1
3 [4, 3, 9, 7]
3 4