import std.math;
  /*
- 
-     Given an array of integers, sort the integers that are between 1 and 9 inclusive,
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+ Given an array of integers, sort the integers that are between 1 and 9 inclusive,
-     reverse the resulting array, and then replace each digit by its corresponding name from
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+ reverse the resulting array, and then replace each digit by its corresponding name from
-     "One", "Two", "Three", "Four", "Five", "Six", "Seven", "Eight", "Nine".
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+ "One", "Two", "Three", "Four", "Five", "Six", "Seven", "Eight", "Nine".
- 
-     For example:
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+ For example:
-     >>> by_length([2L, 1L, 1L, 4L, 5L, 8L, 2L, 3L])
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+ >>> by_length([2L, 1L, 1L, 4L, 5L, 8L, 2L, 3L])
-     ["Eight", "Five", "Four", "Three", "Two", "Two", "One", "One"]
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+ ["Eight", "Five", "Four", "Three", "Two", "Two", "One", "One"]
-     
-       If the array is empty, return an empty array:
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+   If the array is empty, return an empty array:
-     >>> by_length([])
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+ >>> by_length([])
+ []
-     []
-     
-       If the array has any strange number ignore it:
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+   If the array has any strange number ignore it:
-     >>> by_length([1L, -1L, 55L])
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+ >>> by_length([1L, -1L, 55L])
-     ["One"]
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+ ["One"]
-     
  */
  string[] by_length(long[] arr)