0/1 1/1
2/1 3/1
4/1 5/1
6/1 7/1
8/1 9/1
10/1 11/1
12/1 13/1
14/1 15/1
16/1 17/1
18/1 19/1
20/1 21/1
2256637/100000 2356637/100000