distribute	reads
0-500	0
500-800	3
800-1000	0
1000-1200	0
1200-1400	1
1400-1600	2
1600-1800	0
1800-2000	0
2000-2200	2
2200-2400	2
2400-2600	0
2600-2800	2
2800-3000	1
>3000	336
