Roman Numerals

Lab Python Advanced 30 points

Read a Roman numeral (I, V, X, L, C, D, M) and print its value. A smaller symbol before a larger one is subtracted (IV = 4).

Input

One valid numeral up to 3999.

Output

The integer value.

Example

Input

XIV

Output

Sample input available Sample output available

Editor

Python

Hints

Map each symbol to its value with a dict.

Subtract a value when the next symbol is larger.

Solution explanation

A dict turns a chain of if statements into one lookup.

Show solution

values = {"I": 1, "V": 5, "X": 10, "L": 50, "C": 100, "D": 500, "M": 1000}
s = input()
total = 0
for i, ch in enumerate(s):
    v = values[ch]
    if i + 1 < len(s) and v < values[s[i + 1]]:
        total -= v
    else:
        total += v
print(total)

Output

Answer