1 array 1 1
2 var 1 valid
3 zero 1
4 one 1

5 next 1 2 4

6 read 1 1 3
7 read 1 1 4
8 write 1 1 1 4 6
9 write 1 1 8 3 7
10 ugt 1 6 7
11 acond 1 1 10 9 1
12 anext 1 1 1 11

13 read 1 1 3
14 read 1 1 4
15 ugt 1 13 14
16 root 1 15