code: def string_of_length(n):
      if n <= 0:
          return ""
      n -= 1
      y = ["", "$(1x10-1)", "$(10x10-1)", "$(100x10-1)", "$(1000x10-1)"]
      result = []
      for i in reversed(xrange(5)):
          x, n = divmod(n, 10**i)
          result += [y[i]] * x
      result.append("x")
      return " ".join(result)
  
imports: import BoostBuild
  import os
  import re
  import sys
label_desc: Use image node_id 1 for calling a global function with example usage: string_of_length(n) and returns: str, str