Question

Design, implement, and fully test a Python3 function that converts a number to words (words_from_number(number: int)). It should expect to be passed a natural number (such as 12345) and return the corresponding words (i.e., “twelve thousand three hundred forty-five”). Since Python integers can grow arbitrarily large, your code should be flexible, handling at least 20 digits (realistically, it’s just as easy up to 30 digits). Spell everything correctly, and use correct punctuation (hyphens for forty-five and thirty-seven, no commas or plurals). You may only use built-in Python functions, not any modules or third-party libraries!

Answer 1

Here is the code fo you:

# Python3 program to print a given number in words.
# The program handles till 9 digits numbers and
# can be easily extended to 20 digit number

# strings at index 0 is not used, it
# is to make array indexing simple
one = [ "", "one ", "two ", "three ", "four ",
       "five ", "six ", "seven ", "eight ",
       "nine ", "ten ", "eleven ", "twelve ",
       "thirteen ", "fourteen ", "fifteen ",
       "sixteen ", "seventeen ", "eighteen ",
       "nineteen "];

# strings at index 0 and 1 are not used,
# they is to make array indexing simple
ten = [ "", "", "twenty ", "thirty ", "forty ",
       "fifty ", "sixty ", "seventy ", "eighty ",
       "ninety "];

# n is 1- or 2-digit number
def numToWords(n, s):

   str = "";
  
   # if n is more than 19, divide it
   if (n > 19):
       str += ten[n // 10] + one[n % 10];
   else:
       str += one[n];

   # if n is non-zero
   if (n):
       str += s;

   return str;

# Function to print a given number in words
def convertToWords(n):

   # stores word representation of given
   # number n
   out = "";

   # handles digits at ten millions and
   # hundred millions places (if any)
   out += numToWords((n // 10000000),
                           "crore ");

   # handles digits at hundred thousands
   # and one millions places (if any)
   out += numToWords(((n // 100000) % 100),
                               "lakh ");

   # handles digits at thousands and tens
   # thousands places (if any)
   out += numToWords(((n // 1000) % 100),
                           "thousand ");

   # handles digit at hundreds places (if any)
   out += numToWords(((n // 100) % 10),
                           "hundred ");

   if (n > 100 and n % 100):
       out += "and ";

   # handles digits at ones and tens
   # places (if any)
   out += numToWords((n % 100), "");

   return out;

# Driver code

# long handles upto 9 digit no
# change to unsigned long long
# int to handle more digit number
n = 438237764;

# convert given number in words
print(convertToWords(n));