Simple Sudoku Helper

3   +   +     +   9   +     +   +   7   +   2   +     +   +   +     +   5   +   +   +   7     +   +   +     8   +   +     +   +   +     3   +   4     +   +   +   1   +   +     +   6   +     +   +   3   +   +   +     7   +   2     +   +   +     +   +   4     +   +   +     2   +   +   +   8   +     +   +   +     +   4   +   9   +   +     +   3   +     +   +   1

Enter some numbers and press "Update" Cells that contain just a number are completed; the only option provided by the drop-down box is bk (for "back") which will un-set the box. Cells that contain a number in square brackets are currently uncompleted; the number shows how many legal entries there are, and the drop-down box permits the selection of one of those legal entries. Get Another One

bk3 [4]1456 [4]1568 [6]124568 bk9 [4]1568 [3]146 [3]126 bk7 [3]468 bk2 [4]1689 [4]1468 [4]1478 [5]13678 [5]13469 bk5 [3]469 [3]456 [5]14569 bk7 [5]12456 [4]1245 [4]1356 bk8 [5]12369 [4]2469 [5]25678 [4]5679 [5]25689 bk3 [3]158 bk4 [5]15679 [6]126789 [5]25689 bk1 [4]4579 [4]2589 [3]589 bk6 [3]589 [4]4579 [4]2789 bk3 [4]4568 [5]34569 [5]35689 bk7 [3]158 bk2 [5]14569 [4]1689 [5]45689 [3]567 [5]13567 bk4 [5]15689 [4]1578 [6]156789 bk2 [5]36789 [4]5689 [4]2567 bk8 [5]12356 [5]12569 [4]1257 [5]15679 [5]35679 bk4 [3]569 bk9 [3]567 [3]256 [5]24568 bk3 [4]5678 [3]567 [3]678 bk1