Online PHP editor | output for 13p4a

<?php $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); $sudoku[] = array(null,null,null, null,null,null, null,7,null); foreach ($sudoku as $column) { foreach ($column as $cell) { echo "|"; if (null !== $cell) { echo $cell; } echo "|\n"; } }