Solver-verified route
- Place Piece 1 across column 5 row 3, column 6 row 3, column 5 row 4.
- Place Piece 2 at column 5, row 2.
- Place Piece 3 at column 5, row 5.
Part of the "Vertical thinking" chapter. The solver certified 6 solving lines with 97% of in-between placements being dead ends, for a difficulty score of 16.0 (grade 2 of 5).