Solves problem 17

e_17.py

@@ -16,11 +16,40 @@
  British usage.
  ##---
 """
-def fun():
+def letters_to_1000():
     """
+    Returns the number of letters used from 1 to 1000
     """
         
-    return 1
+    number_of_hundreds = 9
+    number_of_ties = 8 * number_of_hundreds # tens are specials
+    number_of_tens = 9
+    number_of_thousands = 1
+    number_of_unities = 10
+    
+    ands = ["and"]
+    numbers = ["one", "two", "three", "four", "five", "six", "seven", "eight", "nine"]
+    tens = ["ten", "eleven", "twelve", "thirteen", "fourteen", "fifteen", "sixteen", "seventeen", "eighteen", "nineteen"] 
+    ties = ["twenty", "thirty", "forty", "fifty", "sixty", "seventy", "eighty", "ninety" ] 
+    hundreds = ["hundred"] 
+    thousands = ["thousand"]
+    
+    andl = char_list(ands) * number_of_hundreds * (100 - 1)
+    numbersl = char_list(numbers) * (number_of_hundreds + 1) * number_of_tens
+    hunpref = 100 * char_list(numbers) # one hundred, two hundred and so on. . . 
+    tensl = char_list(tens) * (number_of_hundreds + 1)
+    tiesl = char_list(ties) * (number_of_hundreds + 1) * number_of_unities
+    hundredsl = char_list(hundreds) * number_of_hundreds * 100
+    thousandsl = char_list(thousands) * number_of_thousands
+    onethousand = 3 # for the "one" thousand
+    
+    return andl + numbersl + tensl + tiesl + hundredsl + thousandsl + hunpref + onethousand
+
+def char_list(list_val):
+    """
+    Returns the total number of characters in a list
+    """
+    return sum([len(val) for val in list_val])
 
 if __name__ == '__main__':
-    print "Answer : %d" % (fun())
+    print "Answer : %d" % (letters_to_1000())