CODE EXAMPLE FOR JAVASCRIPT

how to convert roman to decimal in javascript

const romanToDecimal = () => {
  const romanToInt = (s) => {
    const legend = "IVXLCDM";
    const l = [1, 5, 10, 50, 100, 500, 1000];
    let sum = 0;
    while (s) {
      if (!!s[1] && legend.indexOf(s[0]) < legend.indexOf(s[1])) {
        sum += l[legend.indexOf(s[1])] - l[legend.indexOf(s[0])];
        s = s.substring(2, s.length);
      } else {
        sum += l[legend.indexOf(s[0])];
        s = s.substring(1, s.length);
      }
    }
    return sum;
  };
  return romanToInt(text.toUpperCase()).toString();
};