121. Convert_decimal_to_roman_numerial.js

//*---- convert decimal to roman numerial

//? Converting a decimal number to roman numerials involves finding the combination of roman numerials symbols that represent the given decimal value.

function decimalToRoman(num) {
  if (!Number.isInteger(num) || num <= 0 || num > 3999) return "invalid input";
  const arrR = [
    { value: 1000, symbol: "M" },
    { value: 900, symbol: "CM" },
    { value: 500, symbol: "D" },
    { value: 400, symbol: "CD" },
    { value: 100, symbol: "C" },
    { value: 90, symbol: "XC" },
    { value: 50, symbol: "L" },
    { value: 40, symbol: "XL" },
    { value: 10, symbol: "X" },
    { value: 9, symbol: "IX" },
    { value: 5, symbol: "V" },
    { value: 4, symbol: "IV" },
    { value: 1, symbol: "I" },
  ];
  let result = "";

  for (const { value, symbol } of arrR) {
    while (num >= value) {
      result += symbol;
      num -= value;
    }
  }
  return result;
}
console.log(decimalToRoman(12));