Seven different symbols represent Roman numerals with the following values:
Symbol
Value
I
1
V
5
X
10
L
50
C
100
D
500
M
1000
Roman numerals are formed by appending the conversions of decimal place values from highest to lowest. Converting a decimal place value into a Roman numeral has the following rules:
If the value does not start with 4 or 9, select the symbol of the maximal value that can be subtracted from the input, append that symbol to the result, subtract its value, and convert the remainder to a Roman numeral.
If the value starts with 4 or 9 use the subtractive form representing one symbol subtracted from the following symbol, for example, 4 is 1 (I) less than 5 (V): IV and 9 is 1 (I) less than 10 (X): IX. Only the following subtractive forms are used: 4 (IV), 9 (IX), 40 (XL), 90 (XC), 400 (CD) and 900 (CM).
Only powers of 10 (I, X, C, M) can be appended consecutively at most 3 times to represent multiples of 10. You cannot append 5 (V), 50 (L), or 500 (D) multiple times. If you need to append a symbol 4 times use the subtractive form.
They said this is medium type question in LeetCode but for me which is easy for me since this question is one of the certificate lessons from freeCodeCamp's Javascript Algorithms and Data Structures Course. I feel easy maybe I have familiar before. But anyway for me Roman to Integer is more difficult. What do yall think?
13000 = MMM as 1000 (M) + 1000 (M) + 1000 (M)
2 700 = DCC as 500 (D) + 100 (C) + 100 (C)
3 40 = XL as 10 (X) less of 50 (L)
4 9 = IX as 1 (I) less of 10 (X)
5Note: 49 is not 1 (I) less of 50 (L) because the conversion is based on decimal places
6
13000 = MMM as 1000 (M) + 1000 (M) + 1000 (M)
2 700 = DCC as 500 (D) + 100 (C) + 100 (C)
3 40 = XL as 10 (X) less of 50 (L)
4 9 = IX as 1 (I) less of 10 (X)
5Note: 49 is not 1 (I) less of 50 (L) because the conversion is based on decimal places
