1. Since there is an arrow from (1,4) to (1,3) and from (1,2) to (2,2), the only possible link to (1,2) (since it cannot be (01)) is from (1,1) to (1,2).

2. This implies that (01), (02), (03), and (04), must be in (1,1), (1,2), (2,1) and (2,2), since having (04) in (3,2) would result in (2,1) not being able to be filled in.

3. Since (04) has to be connected to (05) in (3,1), (04) must thus be placed in (2,1).

4. This implies that (03) has to be placed in (2,2).​

5. This implies that (02) has to be placed in (2,1).

6. This implies that (01) has to be placed in (1,1).

7. (06) can be placed in either (3,2) or (4,1). However, placing (06) in (3,2) means that (07) must be placed in (3,3), to ensure that (4,1) can be filled in. However, from there, it is not possible to connect it to (11). Hence, (06) must be placed in (4,1).

8. This implies that (07) has to be placed in (4,2). 

9. (08) could be placed in (3,2) or (4,3), but having it in (4,2) means that (09) must be placed in (3,3) and (10) must be placed in (3,4). However, the puzzle cannot be solved from there. Thus, (08) must be placed in (4,3).

10. (09) could be placed in either (4,4) or (3,3), but again, placing it in (3,3) does not allow (4,4) to be filled. Thus, (09) must be placed in (4,4). 

11. This implies that (10) must be placed in (3,4).

12. (16) must be placed in (3,2) as it is a dead end.

13. This implies that (15) must be placed in (3,3).

14. This implies that (14) must be placed in (2,3).

15. This implies that (13) must be placed in (1,3).

16. This implies that (12) must be placed in (1,4).

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