Man writing.
Photo by Paul Van Hemel

When - completed

This event was held on Wednesday, September 18.

Results and Records

See the results of the NVSO 2019 sudoku event.


General Rules
Please go here for rules covering all events.

Sudoku Rules
Competition will be in 10-year age groups (50-59, 60-69, 70-79, 80-89, 90-99, 100+) with no gender divisions. NVSO will provide the Logic Puzzles and pencils.

A) General

  • Logic Puzzles will be a 9×9 grid of 81 cells subdivided into nine 3×3 boxes with between 24 and 34 of these cells prefilled with a number from 1 to 9 as initial clues. The object is to place a single number (1-9) in each empty cell such that the completed puzzle does not repeat any number in any of the nine rows, columns or boxes, and to do so in the shortest time possible.
  • The event consists of a series of five increasingly difficult puzzles to solve:

    Two with 15 minute limits,

    Two with 20 minute limits,

    One with a 30 minute limit.
  • Contestants may only use a pencil for notations and their own brainpower to solve the puzzles. Computer/smart phone analysis or cribbing off of other contestant are prohibited. However, notations and guessing are allowed as long as it remains clear which single number goes with each cell.
  • Once a puzzle is completed, a contestant will raise his/her hand and a proctor will record his/her elapsed time and collect the puzzle for grading.
  • At the end of the allotted time for a puzzle round any remaining unfinished puzzles will be collected for grading and recording the total time (15, 20, or 30 minutes) for that round. 

B) Grading

  • Cells with two or more numbers, the wrong number, and cells left entirely unmarked are graded as mistakes and assessed a 1 minute time penalty each, which is added to the contestant’s completion time for that puzzle.
  • The cumulative time required to complete all five puzzles, including assessed time penalties for mistakes, is the contestant’s score, with the winner in each age group being the contestant with the lowest total score. If more than one competitor made the same number of mistakes (0 or more), the competitors are graded in each group having made the same number of mistakes by the least cumulative time used to solve all puzzles. 

C) Awards

  • Gold, Silver and Bronze medals are awarded to the contestants in each age group.