Aromatic Numbers
This question involves calculating the value of aromatic numbers which are a combination of Arabic digits and Roman numerals.
An aromatic number is of the form ARARAR…AR, where each A is an Arabic digit, and each R is a Roman numeral. Each pair AR contributes a value described below, and by adding or subtracting these values together we get the value of the entire aromatic number.
An Arabic digit A can be 0, 1, 2, 3, 4, 5, 6, 7, 8 or 9. A Roman numeral R is one of the seven letters I, V, X, L, C, D, or M. Each Roman numeral has a base value:
| Symbol | I | V | X | L | C | D | M |
|---|---|---|---|---|---|---|---|
| Base value | 1 | 5 | 10 | 50 | 100 | 500 | 1000 |
The value of a pair AR is A times the base value of R. Normally, you add up the values of the pairs to get the overall value. However, wherever there are consecutive symbols ARA′R′ with R′ having a strictly bigger base value than R, the value of pair AR must be subtracted from the total, instead of being added .
For example, the number 3M1D2C has the value 3×1000+1×500+2×100=3700 and 3X2I4X has the value 3×10−2×1+4×10=68.
Write a program that computes the values of aromatic numbers.
Input Specification
The input is a valid aromatic number consisting of between 2 and 20 symbols.
Output Specification
The output is the decimal value of the given aromatic number.
Sample Input 1
3M1D2C
Output for Sample Input 1
3700
Sample Input 2
2I3I2X9V1X
Output for Sample Input 2
-16