1. 替换那些使用减法记法书写的符号组。
用其他仅使用加法表示法编写的数字组替换以减法表示法编写的那些数字组.
IV:
IV = V - I = IIIII - I = IIII
IV = IIII
IX:
IX = X - I = V IIIII - I = V IIII = VIIII
IX = VIIII
XL:
XL = L - X = XXXXX - X = XXXX
XL = XXXX
XC:
XC = C - X = L XXXXX - X = L XXXX = LXXXX
XC = LXXXX
CD:
CD = D - C = CCCCC - C = CCCC
CD = CCCC
CM:
CM = M - C = D CCCCC - C = D CCCC = DCCCC
CM = DCCCC
M(V):
M(V) = (V) - M = MMMMM - M = MMMM
M(V) = MMMM
3. 按降序排列符号。
按照从左到右的降序排列符号,左边最大的符号,右边最小的符号。
IIIIIIIIIIVVIVIIVIIIVIIIIXXXXXXXXXXLLXLXXLXXXLXXXXCCCCCCCCCCDDCDCCDCCCDCCCCMMMMMMMMMM(V)(V)M(V)M =
(V)(V)(V)MMMMMMMMMMMMDDDDDCCCCCCCCCCCCCCCCCCCCLLLLLXXXXXXXXXXXXXXXXXXXXVVVVVIIIIIIIIIIIIIIIIIIII
4. 将所有重复符号合并在一起。
从数字的右端开始 (从较小的值开始) 并将重复的符号合并为较大的符号。
(V)(V)(V)MMMMMMMMMMMMDDDDDCCCCCCCCCCCCCCCCCCCCLLLLLXXXXXXXXXXXXXXXXXXXXVVVVVIIIIIIIIIIIIIIIIIIII =
(V)(V)(V)MMMMMMMMMMMMDDDDDCCCCCCCCCCCCCCCCCCCCLLLLLXXXXXXXXXXXXXXXXXXXXVVVVVIIIII IIIII IIIII IIIII =
(V)(V)(V)MMMMMMMMMMMMDDDDDCCCCCCCCCCCCCCCCCCCCLLLLLXXXXXXXXXXXXXXXXXXXXVVVVVVVVV =
(V)(V)(V)MMMMMMMMMMMMDDDDDCCCCCCCCCCCCCCCCCCCCLLLLLXXXXXXXXXXXXXXXXXXXXVVVVVVVVV =
(V)(V)(V)MMMMMMMMMMMMDDDDDCCCCCCCCCCCCCCCCCCCCLLLLLXXXXXXXXXXXXXXXXXXXXVV VV VV VV V =
(V)(V)(V)MMMMMMMMMMMMDDDDDCCCCCCCCCCCCCCCCCCCCLLLLLXXXXXXXXXXXXXXXXXXXXXXXXV =
(V)(V)(V)MMMMMMMMMMMMDDDDDCCCCCCCCCCCCCCCCCCCCLLLLLXXXXXXXXXXXXXXXXXXXXXXXXV =
(V)(V)(V)MMMMMMMMMMMMDDDDDCCCCCCCCCCCCCCCCCCCCLLLLLXXXXX XXXXX XXXXX XXXXX XXXXV =
(V)(V)(V)MMMMMMMMMMMMDDDDDCCCCCCCCCCCCCCCCCCCCLLLLLLLLLXXXXV =
(V)(V)(V)MMMMMMMMMMMMDDDDDCCCCCCCCCCCCCCCCCCCCLLLLLLLLLXXXXV =
(V)(V)(V)MMMMMMMMMMMMDDDDDCCCCCCCCCCCCCCCCCCCCLL LL LL LL LXXXXV =
(V)(V)(V)MMMMMMMMMMMMDDDDDCCCCCCCCCCCCCCCCCCCCCCCCLXXXXV =
(V)(V)(V)MMMMMMMMMMMMDDDDDCCCCCCCCCCCCCCCCCCCCCCCCLXXXXV =
(V)(V)(V)MMMMMMMMMMMMDDDDDCCCCC CCCCC CCCCC CCCCC CCCCLXXXXV =
(V)(V)(V)MMMMMMMMMMMMDDDDDDDDDCCCCLXXXXV =
(V)(V)(V)MMMMMMMMMMMMDDDDDDDDDCCCCLXXXXV =
(V)(V)(V)MMMMMMMMMMMMDD DD DD DD DCCCCLXXXXV =
(V)(V)(V)MMMMMMMMMMMMMMMMDCCCCLXXXXV =
(V)(V)(V)MMMMMMMMMMMMMMMMDCCCCLXXXXV =
(V)(V)(V)MMMMM MMMMM MMMMM MDCCCCLXXXXV =
(V)(V)(V)(V)(V)(V)MDCCCCLXXXXV =
(V)(V)(V)(V)(V)(V)MDCCCCLXXXXV =
(V)(V) (V)(V) (V)(V)MDCCCCLXXXXV =
(X)(X)(X)MDCCCCLXXXXV