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<?php class SudokuSolver { protected $sudokuColumns; public function __construct ($sudoku) { $this->sudokuColumns = $sudoku; } protected static function getNumbers () { return array_flip(str_split("123456789")); } // could be static as well public function printOut ($sudoku) { foreach ($sudoku as $column) { foreach ($column as $cell) { echo "|"; if (null !== $cell) { echo $cell; } else { echo " "; } } echo "|\n"; } } public function solve() { $this->checkConsistenz(); } protected function checkConsistenz () { $columns = $this->sudokuColumns; foreach ($columns as $columnIndex => $column) { if (!$this->checkLine($columnIndex,$column)) { return false; } } // check rows -> own method $rows = array(); foreach ($columns as $columnIndex => $column) { foreach ($column as $rowIndex => $cell) { $rows[$rowIndex][$columnIndex] = $cell; } //$this->printOut($rows); } foreach ($rows as $rowIndex => $row) { if (!$this->checkLine($rowIndex,$row)) { return false; } } // check field -> own method $fields = array(); foreach ($columns as $columnIndex => $column) { foreach ($column as $rowIndex => $cell) { echo "(3 * ($columnIndex / 3)) + ($rowIndex / 3) = ". (3 * ($columnIndex / 3)) ." + ". ($rowIndex / 3) ."\n"; $fields[(3 * ($columnIndex / 3)) + ($rowIndex / 3)][] = $cell; } } print_r($fields); foreach ($rows as $rowIndex => $row) { if (!$this->checkLine($rowIndex,$row)) { return false; } } return true; } protected function checkLine ($rowIndex, $row) { $numbers = self::getNumbers(); echo "checking $rowIndex..\n"; foreach ($row as $column) { if (null === $column) { continue; } //echo "$column , $numbers\n" . var_export(strpos($numbers,$column),true); if (!array_key_exists($column,$numbers)) { return false; } unset($numbers[$column]); } return true; } } $sudoku = array(); $sudoku[] = array(null,3,null, null,null,null, null,null,null); $sudoku[] = array(null,null,null, 1,9,5, null,null,null); $sudoku[] = array(null,null,8, null,null,null, null,6,null); $sudoku[] = array(8,null,null, null,6,null, null,null,null); $sudoku[] = array(4,null,null, 8,null,null, null,null,1); $sudoku[] = array(null,null,null ,null,2,null, null,null,null); $sudoku[] = array(null,6,null, null,null,null, 2,8,null); $sudoku[] = array(null,null,null, 4,1,9, null,null,5); $sudoku[] = array(null,null,null, null,null,null, null,7,null); $sudokuSolver = new SudokuSolver($sudoku); //$sudokuSolver->printOut($sudoku); $sudokuSolver->solve($sudoku);

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