freeCodeCamp

mirror of https://github.com/freeCodeCamp/freeCodeCamp.git

title
Roman Numerals

Roman Numerals

I = 1
V = 5
X = 10
L = 50
C = 100
D = 500
M = 1000

How to Remember:
"M e D i C a L X a V I e r".
It has the roman numerals in descending order from 1000 to 1.

When a symbol appears after a larger (or equal) symbol, it is added:

Example:
II = 2, (1 + 1 = 2)
VI = 6, (5 + 1 = 6)
XI = 11, (10 + 1 = 11)

But if a symbol appears before a larger symbol, it is subtracted:

Example:
IV = 4, (5 - 1 = 4)
IX = 9, (10 - 1 = 9)

Don't use the same symbol more than three times in a row:

Example:
III = 3
VIII = 8
XXX = 30
LXXX = 80
CCC = 300
DCCC = 800
MMM = 3000