Level 72 solution

Solver-verified route

1. Place Piece 1 across column 1 row 3, column 1 row 4.
2. Place Piece 2 across column 2 row 3, column 2 row 4.
3. Place Piece 3 across column 1 row 5, column 2 row 5, column 1 row 6.

Part of the "Vertical thinking" chapter. The solver certified 12 solving lines with 93% of in-between placements being dead ends, for a difficulty score of 14.1 (grade 1 of 5).