# WPC 2019/Round 4

Duration: 30 minutes. Total point value: 250 points. Round winner: Kota Morinishi (Japan), 380 points.

### Puzzle[edit]

The puzzle was written by Roland Voigt. This was a combination puzzle.

This round consists of one large puzzle, consisting of six small puzzles (6×6 grids) interacting with each other via outside clue numbers. 6 puzzles were:

- Battleships
- Sudoku
- The numbers outside the grid indicate the difference of the first two numbers in the respective row or column, seen from the respective direction.

- Doppelblock Skyscrapers
- First Seen Coral
- Slitherlink
- The numbers outside the grid indicate how many cells in the respective row or column are inside the loop.

- Tents

These six puzzles are arranged in a 3×2 pattern, so that outside clues at the interior borders can refer to two puzzles. If such a position is marked with a rectangular box, then the same clue number is valid for both puzzles according to the rules above. All possible boxes are given, which means that in all positions without a box, the respective clue numbers must be different.

The example is from WPC 2019 IB.

### Partial Scoring[edit]

If this round is completely solved, the competitor will receive 250 points.

In a partially solved puzzle, competitors will receive points for interior clues (that is, outside clue numbers between two puzzles). Each clue number in a marked spot that is valid for both puzzles is worth 5 points; clue numbers in all other spots are worth 2 points. Furthermore, competitors will receive 10 points for each completely solved grid.

If any of the six small puzzles are correctly solved, all clue numbers adjacent to these puzzles are automatically considered correct, and all points for these clues are awarded. This does not apply when a solution contains a mistake, however small; to receive partial points in such a situation we recommend to write down all clue numbers even when the puzzle is completely solved.