Japan's Kaji, the "godfather of Sudoku," dies at 69.

Japan's Kaji, the "godfather of Sudoku," dies at 69.
Maki Kaji, a puzzle enthusiast and publisher who was known as the "Godfather of Sudoku" - the number puzzle played daily by millions around the world - has died, his company said.
He was 69.
A university dropout who worked in a printing company before founding Japan's first puzzle magazine, Kaji took hints from an existing number puzzle to create what he later named "sudoku" - a contraction of the Japanese for "every number must be single" - sometime in the mid-80s.
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The logic puzzle challenges people to fill a grid of 9X9 blocks, with nine boxes in each block so that all columns, both vertical and horizontal, contain the numbers 1 to 9 without repetition.
The number of filled-in figures for a grid at the start of the puzzle determines how difficult it is.
"Known as the Godfather of Sudoku, he was adored by puzzle lovers around the world and we would like to express our gratitude to all of you," his company, Nikoli, said on its website on Monday.