var romanToInt = function (s) {
const map = [
["I", "V", 'X'],
["X", "L", 'C'],
["C", "D", 'M'],
["M", '', ''],
]
const str = String(s)
let res = []
let resStr = ''
for (let i = str.length; i > 0; i--) {
if (str[i - 1] >= 5) {
//等于9
if (str[i - 1] == 9) {
// res += map[str.length - i][0] + map[str.length - i][2]
res.push(map[str.length - i][0] + map[str.length - i][2])
continue
}
if (str[i - 1] == 5) {
res.push(map[str.length - i][1])
continue
}
//不等于9
let curr = ''
for (let j = 0; j < str[i - 1] - 5; j++) {
curr += map[str.length - i][0]
}
//res += map[str.length - i][2] + curr
res.push(map[str.length - i][2] + curr)
} else {
//等于4
if (str[i - 1] == 4) {
//res += map[str.length - i][0] + map[str.length - i][1]
res.push(map[str.length - i][0] + map[str.length - i][1])
continue
}
//不等于4
let curr = ''
for (let j = 0; j < str[i - 1]; j++) {
curr += map[str.length - i][0]
}
//res += curr
res.push(curr)
}
}
for (let i = res.length; i > 0; i--) {
resStr += res[i - 1]
}
return resStr
};