RosettaCodeData/Task/Last-letter-first-letter/Ruby/last-letter-first-letter.rb
Ingy döt Net 6f050a029e update
2013-06-05 21:47:54 +00:00

41 lines
1.5 KiB
Ruby

class LastL_FirstL
def initialize(names)
@names = names.dup
@first = names.group_by {|name| name[0]}
@sequences = []
end
def add_name(seq)
last_letter = seq[-1][-1]
potentials = @first.include?(last_letter) ? (@first[last_letter] - seq) : []
if potentials.empty?
@sequences << seq
else
potentials.each {|name| add_name(seq + [name])}
end
end
def search
@names.each {|name| add_name [name]}
max = @sequences.max_by {|seq| seq.length}.length
max_seqs = @sequences.select {|seq| seq.length == max}
puts "there are #{@sequences.length} possible sequences"
puts "the longest is #{max} names long"
puts "there are #{max_seqs.length} such sequences. one is:"
max_seqs.last.each_with_index {|name, idx| puts " %2d %s" % [idx+1, name]}
end
end
names = %w{
audino bagon baltoy banette bidoof braviary bronzor carracosta charmeleon
cresselia croagunk darmanitan deino emboar emolga exeggcute gabite
girafarig gulpin haxorus heatmor heatran ivysaur jellicent jumpluff kangaskhan
kricketune landorus ledyba loudred lumineon lunatone machamp magnezone mamoswine
nosepass petilil pidgeotto pikachu pinsir poliwrath poochyena porygon2
porygonz registeel relicanth remoraid rufflet sableye scolipede scrafty seaking
sealeo silcoon simisear snivy snorlax spoink starly tirtouga trapinch treecko
tyrogue vigoroth vulpix wailord wartortle whismur wingull yamask
}
lf = LastL_FirstL.new(names)
lf.search