examples/rosettacode/symmetric_difference.nit

   1 #!/usr/bin/env nit
   2 #
   3 # This file is part of NIT ( http://www.nitlanguage.org ).
   4 # This program is public domain
   5
   6 # Task: Symmetric difference
   7 # SEE: <http://rosettacode.org/wiki/Symmetric_difference>
   8
   9 module symmetric_difference
  10
  11 var a = ["John", "Serena", "Bob", "Mary", "Serena"]
  12 var b = ["Jim", "Mary", "John", "Jim", "Bob"]
  13
  14 print "Set A: {a.join(", ")}"
  15 print "Set B: {b.join(", ")}"
  16
  17 # Option 1: union of differences
  18 var not_in_a = new ArraySet[String]
  19 not_in_a.add_all(b)
  20 for x in a do
  21         not_in_a.remove_all(x)
  22 end
  23
  24 var not_in_b = new ArraySet[String]
  25 not_in_b.add_all(a)
  26 for x in b do
  27         not_in_b.remove_all(x)
  28 end
  29
  30 var difference = not_in_a.clone
  31 difference.add_all(not_in_b)
  32
  33 print "Symmetric difference: {difference.join(", ")}"
  34
  35 # Option 2: union minus intersection
  36 var union = new ArraySet[String]
  37 union.add_all(a)
  38 union.add_all(b)
  39
  40 var b1 = new ArraySet[String]
  41 b1.add_all(b)
  42
  43 var intersect
  44 intersect = new ArraySet[String]
  45 intersect.add_all(a)
  46 intersect = intersect.intersection(b1)
  47
  48 var difference2 = union.clone
  49 for x in intersect do
  50         difference2.remove_all(x)
  51 end
  52
  53 print "Symmetric difference: {difference2.join(", ")}"