10
1 1 1 1 1 1 1 1 1 1
1 1 1 2 1 1 2 1 1 1
1 2 1 3 1 1 3 1 1 1
1 3 1 4 1 1 4 1 1 1
1 4 1 5 1 1 1 1 1 1
1 5 1 6 1 1 1 1 1 1
1 1 1 7 8 9 1 1 1 1
1 1 1 1 1 1 1 1 1 1
1 1 1 1 1 5 4 3 2 1
1 1 1 1 1 1 1 1 1 1