Place the five tetrominos given in the left grid into the right grid. Tetrominos may be rotated and reflected. For each arrow, the number determines the number of cells with a tetromino the arrow points at. Tetrominos must not touch, not even diagonally.
Afterwards, draw a closed loop into the grid leading from the center of a cell to the center of a vertically or horizontally adjacent cell. The loop passes every empty cell exactly one time. Empty cells are cells occupied by neither a tetromino nor a number.
Solution code: For every row from top to bottom the number of cells in which the loop bends.
on 14. January 2014, 22:02 by usp
Minor corrections in the instructions
on 14. January 2014, 21:03 by Richard
Nice one!