KAKURO is one of the oldest grid logic puzzles in existence traced back to the April/May 1950 issue of Official Crossword Puzzles by Dell Publishing Company in US. Initially titled Cross Sums or Cross Addition, the puzzle traveled to Japan where it became a great success. Here it changed its name to Kasan Kurosu – a combination of the Japanese word for “addition” and the Japanese pronunciation of the English word “cross.” In 1986 it changed the name again to the abbreviated KaKuro. The puzzle became a hit a around the world and its popularity in Japan is second only to Sudoku.
“Kakuro is Japan’s best-kept secret, a puzzle that millions prefer to Sudoku”
(The new grid on the block, Justin McCurry, The Guardian, Sep 14, 2005)
- Put numbers from 1 through 9 in each cell (No zeros).
- A number in a cell divided by a diagonal line tells the sum of the numbers in the consecutive cells to its right or downward.
- No number may appear more than once in consecutive cells.