This hanjie has a nice technical interest.
You can use what I named wave-logic:
- There are four 1 in column C22, but only three in C21. Then, there is one (or more) row in which there is a black square in C22 and a cross in C21. As the last segment is to long in the other rows, the only row where it is possible is R5. We can thus place the 3.
In this way, we can also place the 5 from R3.
- You can adapt this method to totally place the 19.

This is wave-logic 1, because there is a second way of using it. We will see it later* ;)

*cf. "Hachure (17)"

Difficulty : *****

Tested, logical.
Wave-logic can be usefull.
Good blackenage.