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-rw-r--r--railties/guides/rails_guides/levenshtein.rb48
1 files changed, 25 insertions, 23 deletions
diff --git a/railties/guides/rails_guides/levenshtein.rb b/railties/guides/rails_guides/levenshtein.rb
index 4010b61e26..f99c6e6ba8 100644
--- a/railties/guides/rails_guides/levenshtein.rb
+++ b/railties/guides/rails_guides/levenshtein.rb
@@ -1,29 +1,31 @@
-module Levenshtein
- # Based on the pseudocode in http://en.wikipedia.org/wiki/Levenshtein_distance.
- def self.distance(s1, s2)
- s = s1.unpack('U*')
- t = s2.unpack('U*')
- m = s.length
- n = t.length
+module RailsGuides
+ module Levenshtein
+ # Based on the pseudocode in http://en.wikipedia.org/wiki/Levenshtein_distance.
+ def self.distance(s1, s2)
+ s = s1.unpack('U*')
+ t = s2.unpack('U*')
+ m = s.length
+ n = t.length
- # matrix initialization
- d = []
- 0.upto(m) { |i| d << [i] }
- 0.upto(n) { |j| d[0][j] = j }
+ # matrix initialization
+ d = []
+ 0.upto(m) { |i| d << [i] }
+ 0.upto(n) { |j| d[0][j] = j }
- # distance computation
- 1.upto(m) do |i|
- 1.upto(n) do |j|
- cost = s[i] == t[j] ? 0 : 1
- d[i][j] = [
- d[i-1][j] + 1, # deletion
- d[i][j-1] + 1, # insertion
- d[i-1][j-1] + cost, # substitution
- ].min
+ # distance computation
+ 1.upto(m) do |i|
+ 1.upto(n) do |j|
+ cost = s[i] == t[j] ? 0 : 1
+ d[i][j] = [
+ d[i-1][j] + 1, # deletion
+ d[i][j-1] + 1, # insertion
+ d[i-1][j-1] + cost, # substitution
+ ].min
+ end
end
- end
- # all done
- return d[m][n]
+ # all done
+ return d[m][n]
+ end
end
end