Geradeweg (1184)

Other names: Straight Loop

Draw a single loop that passes orthogonally through centers of cells. The loop cannot intersect itself or enter the same cell more than once.
The loop must go through all cells with a number. Every maximally straight segment in the loop (that is, a section of the loop between two consecutive turns of the loop) that is partially contained in a numbered cell must have its length equal to that number.

Reference: WPF (1)