Roman to Integer

Convert a Roman numeral string to its integer value.

Code

Utilities

const values = { I: 1, V: 5, X: 10, L: 50, C: 100, D: 500, M: 1000 };
let result = 0;
for (let i = 0; i < roman.length; i++) {
  const curr = values[roman[i]], next = values[roman[i + 1]] || 0;
  result += curr < next ? -curr : curr;
}
return result;

Parameters

roman(string)

Roman numeral.

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