theme

Write a method that takes arabic numerals and returns roman numerals [^ pine].

Letters used in Roman numerals

arabic numerals	roman numerals
1	I
5	V
10	X
50	L
100	C
500	D
1000	M

Example

arabic numerals	roman numerals
1	I
2	II
4	IV
5	V
6	VI
9	IX
10	X
11	XI
14	XIV
15	XV
19	XIX
38	XXXVIII
42	XLII
49	XLIX
51	LI
97	XCVII
99	XCIX
439	CDXXXIX
483	CDLXXXIII
499	CDXCIX
732	DCCXXXII
961	CMLXI
999	CMXCIX
1999

Last

# coding: utf-8
def romanize(number)
  a=[1000,900,500,400,100,90,50,40,10,9,5,4,1]
  r=["M","CM","D","CD","C","XC","L","XL","X","IX","V","IV","I"]
  roman=[]

  number=number.to_i

  if (number > 0 and number < 4000) then
    for i in 0..12 do
      while number>=a[i] do
	roman.push(r[i])
	number-=a[i]
      end
    end
  else
    puts "Cannot be converted"
  end

  puts roman.join(' ')
end



puts "Please enter Arabic numerals"
n=gets
romanize(n)

development

Integers are Integer classes. Refer to hello class and extend Integer class to

999.to_roman #=> CMXCIX

Please return.

# coding: utf-8
def romanize(number)
  a=[1000,900,500,400,100,90,50,40,10,9,5,4,1]
  r=["M","CM","D","CD","C","XC","L","XL","X","IX","V","IV","I"]
  roman=[]

  number=number.to_i

  if (number > 0 and number < 4000) then
    for i in 0..12 do
      while number>=a[i] do
	roman.push(r[i])
	number-=a[i]
      end
    end
  else
    puts "Cannot be converted"
  end

  puts roman.join(' ')
end



puts "Please enter Arabic numerals"
n=gets
romanize(n)

References

[^ pine]: "First Programming", Chris Pine (Author), Shin Nishiyama (Translation), O'Reilly Japan (2006/7/24).

source ~/grad_members_20f/members/NobuakiMori/ex_roman_numerals.org