Smashed Sums by Murat Can Tonta
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Theme: Ten’s Complement
Author/Opus: This is the 206th puzzle from our contributing puzzlemaster Murat Can Tonta.
Rules: Fill each row and column of the grid with the digits 1 to 4 and two blackened cells. Numbers outside the grid indicate the sum of the digits between the two blackened cells in that row or column. Blackened cells are allowed to touch. Or see here.
Difficulty: 2.5 stars
Time Standards (highlight to view): Grandmaster = 2:15, Master = 3:00, Expert = 6:00
Solution: PDF; a solution video is also available here.
Note: Follow this link for other less common Number Placement puzzles.