How to multiply Roman numerals?

Question

How to multiply Roman numerals? I need an algorithm of multiplication of numbers written in Roman numbers. Help me please.

Answer 1

Make a table with two columns, and enter the two numbers to be multiplied into the first row. Make the next row by halving the first number (discarding remainders) and doubling the second. Continue until there is nothing left to halve. Cross out all the rows where the left number is even. Add the remaining numbers in the second column. The result is the product of the first two numbers

Examples

Source

Answer 2

Take the first number you want to multiply and break it down into parts, any way you choose. E.G. 43 = XLIII = XL + III, or X + X + X + X + III, etc. Do the same with the second number in the multiplication. E.G. 15 = XV = X + V, or V + V + V, etc.

Take any pair of those combinations and set them within a table, with the higher row showing the first number's parts, and the lower row showing the second number's parts. Multiply starting from the lower right to the upper row, then the lower left to the upper row. Place the result to each equation underneath, vertically.
Total them.