examples/rosettacode/arithmetic_mode.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: Arithmetic mode
   7 # SEE: <http://rosettacode.org/wiki/Averages/Mode>
   8 module arithmetic_mode
   9
  10 # Computes the mode or the `array` values.
  11 #
  12 # FIXME: Only the first mode will be returned, should we return an array of modes?
  13 fun mode(array: Array[Int]): nullable Int do
  14         var seen = new HashMap[Int, Int]
  15         for i in array do
  16                 if not seen.has_key(i) then seen[i] = 0
  17                 seen[i] += 1
  18         end
  19         var max_key = null
  20         var max_val = 0
  21         for k, v in seen do
  22                 if v > max_val then
  23                         max_key = k
  24                         max_val = v
  25                 end
  26         end
  27         return max_key
  28 end
  29
  30 print mode([1, 3, 6, 6, 6, 6, 7, 7, 12, 12, 17]) or else "null"
  31 print mode([1, 1, 2, 4, 4]) or else "null"
  32 print mode([1, 3, 6, 6, 6, 6, 7, 7, 12, 12, 17]) or else "null"
  33 print mode([1, 1, 2, 4, 4]) or else "null"