Sudoku XV

Sudoku XV is a variant of the classic Sudoku puzzle with additional rules: 1. Fill the 9×9 grid with digits 1-9 so that each column, each row, and each of the nine 3×3 boxes contains all the digits from 1 to 9 without repetition. 2. If two adjacent cells are connected by a Roman numeral "X", the sum of the digits in these two cells must be exactly 10. 3. If two adjacent cells are connected by a Roman numeral "V", the sum of the digits in these two cells must be exactly 5. 4. If two adjacent cells have no Roman numeral between them, the sum of their digits cannot be 5 or 10. These additional constraints make the puzzle more challenging and often reduce the number of possible solutions to just one.

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