Question

(Python)

Using these lists:

ones = [ "I","II","III","IV","V","VI","VII","VIII","IX" ]
tens = [ "X", "XX","XXX", "XL", "L", "LX", "LXX", "LXXX", "XC" ]
hundreds = [ "C", "CC", "CCC", "CD", "D", "DC", "DCC", "DCCC", "CM","M" ]

Convert these list to named tuples and store them in a class. Then write a member function(s) for the class to convert a 'int' to a 'roman numeral'. in the range of 1 to 1000. Use comprehensions, map, reduce or join where appropriate.

Answer 1

• A class named Roman will be defined to convert an int to roman number
• firstly, define all the lists given in question as tuples.
• The integer has to be passed as an argument to the contructor.
• The constructor must call a function named covert() that will convert the integer stored in class to roman numeral
• convert() will follow this process:
  • set self.r to an empty string
  • if self.i//100 != 0(the hundreds digit of integer), then append the hundreds[integer//100 - 1] to self.r
  • if (self.i%100)//10!=0 (the second digit of integer) , then append tens[(self.i%100)//10 - 1] to self.r
  • if self.i % 10 != 0(the unit digit of integer), then append[self.i%10 - 1] to self.r
• define a __str__() function that returns self.r

program:

class Roman:
def __init__(self,i):
self.ones = tuple([ "I","II","III","IV","V","VI","VII","VIII","IX" ])
self.tens = tuple([ "X", "XX","XXX", "XL", "L", "LX", "LXX", "LXXX", "XC" ])
self.hundreds = tuple([ "C", "CC", "CCC", "CD", "D", "DC", "DCC", "DCCC", "CM","M" ])
self.i = i
self.convert()

def convert(self):
self.r = ""
if(self.i//100!=0):
self.r = self.r+ self.hundreds[self.i//100 - 1]
if((self.i%100)//10!=0):
self.r = self.r + self.tens[(self.i%100)//10 - 1]
if((self.i%10)!=0):
self.r = self.r + self.ones[self.i%10 - 1]

def __str__(self):
return self.r

i = int(input("Enter a integer between 1 and 1000: "))
R1 = Roman(i)
print(f"{i} in roman numerals is {R1}")

sample input and output: