>>145
Ruby で速いなら、ほかのではもっと速い?

Squeak 3.6

Tarai class >> x: x y: y z: z
 x value <= y value ifTrue: [^ y value].
 ^ Tarai
  x: [Tarai x: [x value - 1] y: y z: z]
  y: [Tarai x: [y value - 1] y: z z: x]
  z: [Tarai x: [z value - 1] y: x z: y]

Time millisecondsToRun: [Tarai x: [64] y: [32] z: [0]]

=> 0.001 / ruby 1.8.1 (2003-12-25) [powerpc-darwin]

速かった…(藁