MIND GAMES
By Scott Kim
HIDATO: PATHS OF REASON
Could this be the next great puzzle craze?
Sudoku puzzles, which had been around under various names for
decades, became an international hit after appearing in The Times of
London in 2004. Now a new number puzzle called Hidato ( hidato.com) is
poised to steal sudoku’s spotlight.
Hidato was invented by an Israeli computer scientist named Gyora
Benedek, who also devised the electronic game Lights Out. He was
inspired to create the puzzle when he was scuba diving one day and saw
a school of sh swim by, ashes of light re ecting off their scales as they
zigzagged through a coral reef. He imagined reconstructing the shes’
crazy swimming patterns by connecting the spots of light. Building on this
inspiration, Benedek created Hidato.
Each Hidato puzzle starts with a grid partially lled with numbers. The
goal is to complete the grid with consecutive numbers so that they connect horizontally, vertically, or diagonally. In the Hidato grid below, the
numbers 1 and 2 touch each other horizontally; the numbers 60 and 61
touch diagonally. As in sudoku, no guesswork is required. Every number
can be deduced by reason. For example, there is only one way to place 3,
4, and 5 in the grid below so that 2 connects to 6. You might also notice
that there is only one possible spot for 42. (You don’t have to place numbers in order. You can work out groups of consecutive numbers and then
gure out the best way to link them.) Can you complete the grid so that
the numbers from 1 to 65 form a continuous path through it?
49
52
59 60
54 56
61
2
1
43 41
39 37
65
45
8
31
6
16
19
24
27
17
23
To solve Hidato efficiently, you need to be able to
visualize the possible paths from one number to the
next. For instance, in the small puzzle below, the 2
could go in either of the starred squares to create one
of two possible paths.
21
1
3
10
6
16 14
1. How many possible paths are there from the 10 to
the 14? (Count all possible paths, even if some of
them do not lead to a complete solution to the grid.)
2. How many possible paths are there from the 3 to
the 6? (Count all possible paths, even if some of
them do not lead to a complete solution.)
3. How many possible paths are there from the 6 to
the 10? (Again, count all possible paths, even if
some of them do not lead to a complete solution.)
4. Solve the whole puzzle. There is a unique
solution.
DO IT YOURSELF
There are three numbers given in the 4-by- 4 Hidato
puzzle below. This puzzle is not completely set up,
though. How many possible locations are there for the
nal number, 16, that lead to a unique solution path?
4
1
7
