21
0	0	-30	10
1	0	-27	10
2	0	-24	10
3	0	-21	10
4	0	-18	10
5	0	-15	10
6	0	-12	10
7	0	-9	10
8	0	-6	10
9	0	-3	10
10	0	0	10
11	0	3	10
12	0	6	10
13	0	9	10
14	0	12	10
15	0	15	10
16	0	18	10
17	0	21	10
18	0	24	10
19	0	27	10
20	0	30	10