Roman numerals

Convert a Roman numeral to an int. The symbols are I=1, V=5, X=10, L=50, C=100, D=500, M=1000. Usually you add, but when a smaller symbol sits before a larger one you subtract it: IV is 4, IX is 9, MCMXCIV is 1994. Scanning from right to left makes the subtract rule easy — subtract any symbol smaller than the one to its right.

Complete romanToInt(String s) converting a Roman numeral to an int. A smaller symbol before a larger one is subtracted, so IV is 4 and MCMXCIV is 1994. Assume valid input.

public class Roman {
    public static int romanToInt(String s) {
        return 0;   // change this
    }
}

Click Run to see the output here.

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Roman numerals

Roman numerals

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