const romanToInt = (s) => {
const roms = {
'I': 1,
'V': 5,
'X': 10,
'L': 50,
'C': 100,
'D': 500,
'M': 1000,
}
const romans = s.split('')
return romans.reduce((acc, curr, i) => roms[curr] < roms[romans[i + 1]] ? acc - roms[curr] : acc + roms[curr], 0)
}