Fizzbuzztination

fizzbuzztination.rb

1.9.3p194 :001 > range = (1..20)
 => 1..20 

1.9.3p194 :002 > fizz = ->(x){ "fizz" if x.modulo(3).zero? }
 => #<Proc:0x007febfc141140@(irb):2 (lambda)> 

1.9.3p194 :003 > buzz = ->(x){ "buzz" if x.modulo(5).zero? }
 => #<Proc:0x007febfc137938@(irb):3 (lambda)> 

1.9.3p194 :004 > fizz_list = range.map(&fizz)
 => [nil, nil, "fizz", nil, nil, "fizz", nil, nil, "fizz", nil, nil, "fizz", nil, nil, "fizz", nil, nil, "fizz", nil, nil] 

1.9.3p194 :005 > buzz_list = range.map(&buzz)
 => [nil, nil, nil, nil, "buzz", nil, nil, nil, nil, "buzz", nil, nil, nil, nil, "buzz", nil, nil, nil, nil, "buzz"] 

1.9.3p194 :006 > fizzbuzz_tuples = fizz_list.zip buzz_list
 => [[nil, nil], [nil, nil], ["fizz", nil], [nil, nil], [nil, "buzz"], ["fizz", nil], [nil, nil], [nil, nil], ["fizz", nil], [nil, "buzz"], [nil, nil], ["fizz", nil], [nil, nil], [nil, nil], ["fizz", "buzz"], [nil, nil], [nil, nil], ["fizz", nil], [nil, nil], [nil, "buzz"]] 

1.9.3p194 :007 > fizzbuzz_list = fizzbuzz_tuples.map(&:join)
 => ["", "", "fizz", "", "buzz", "fizz", "", "", "fizz", "buzz", "", "fizz", "", "", "fizzbuzz", "", "", "fizz", "", "buzz"] 

.9.3p194 :008 > string_or_number = ->(string, index){ string.length.zero? ? (index+1).to_s : string }
 => #<Proc:0x007febfc18ff70@(irb):18 (lambda)> 

1.9.3p194 :009 > output = fizzbuzz_list.each_with_index.map(&string_or_number)
 => ["1", "2", "fizz", "4", "buzz", "fizz", "7", "8", "fizz", "buzz", "11", "fizz", "13", "14", "fizzbuzz", "16", "17", "fizz", "19", "buzz"] 

1.9.3p194 :010 > range.find_all(&fizz)
 => [3, 6, 9, 12, 15, 18] 

1.9.3p194 :011 > range.find_all(&buzz)
 => [5, 10, 15, 20] 

1.9.3p194 :012 > intersection = range.find_all(&fizz) & range.find_all(&buzz)
 => [15]