Convert Arabic numerals to Roman

Roman numerals are a numeral system that uses letters of the Latin alphabet to represent numbers, with seven basic symbols carrying fixed values: I, V, X, L, C, D and M. It is an additive and subtractive system rather than a positional one, so the value of a number comes from combining these symbols instead of relying on the place of each digit.

Symbols are normally written from largest to smallest and added together, but a smaller numeral placed before a larger one signals subtraction, which is how the system keeps long numbers reasonably short. The form used today was refined in the Middle Ages from the notation of ancient Rome, where numbers such as four and nine were once written out in full as repeated symbols. Because there is no symbol for zero and no simple way to show fractions, Roman numerals are awkward for calculation and were long ago replaced by Arabic numerals for everyday arithmetic. Even so, they remain widely used for decorative and formal purposes, such as clock faces, book chapters, the names of monarchs and popes, film release years and the numbering of major events. Converting an ordinary Arabic number into Roman form is therefore a handy way to add a classic, timeless touch or simply to understand inscriptions and dates you come across.