15
20
20
21
21
21
16
21
21
17
21
16
17
21
16
16
18
21
21
21
16
21
21
21
13
21
21
20
21
16
16
16
21
21
16
12
20
16
21
15
21
21
16
21
21
21
21
20
21
21
17
21
21
21
20
21
15
21
21
21
21
12
15
21
21
21
21
21
20
21
21
21
21
21
21
21
21
20
21
21
21
21
21
21
21
21
18
16
21
12
21
16
16
21
21
16
16
21
21
21