2007-05-08 メモ[Ruby] irb(main):002:0> a = [1,2,3,4,5,6] => [1, 2, 3, 4, 5, 6] irb(main):003:0> b = [2,4,6] => [2, 4, 6] irb(main):004:0> a -b => [1, 3, 5] 配列の引き算できるのね