convert roman numeral to number javascript

1function convertToRoman(num) {
2var numeral = "";
3 var arr = [
4 {number:1, roman: "I"},
5 {number:4, roman: "IV"},
6 {number:5, roman: "V"},
7 {number:9, roman: "IX"},
8 {number:10, roman: "X"},
9 {number:40, roman: "XL"},
10 {number:50, roman: "L"},
11 {number:90, roman: "XC"},
12 {number:100, roman: "C"},
13 {number:400, roman: "CD"},
14 {number:500, roman: "D"},
15 {number:900, roman: "CM"},
16 {number:1000, roman: "M"}
17 ]
18 while(num > 0){
19  var searching = arr.filter(function(myArr){
20    if(myArr.number <= num){
21      return myArr.number
22    }
23  })
24  var latest = searching.pop()
25  var full = Math.floor(num / latest.number)
26  for(let i = 0; i<full; i++){
27    numeral +=latest.roman
28  }
29  num = num % latest.number
30 }
31 return numeral 
32}
33
34console.log(convertToRoman(36));

1function roman_to_Int(str1) {
2if(str1 == null) return -1;
3var num = char_to_int(str1.charAt(0));
4var pre, curr;
5
6for(var i = 1; i < str1.length; i++){
7curr = char_to_int(str1.charAt(i));
8pre = char_to_int(str1.charAt(i-1));
9if(curr <= pre){
10num += curr;
11} else {
12num = num - pre*2 + curr;
13}
14}
15
16return num;
17}
18
19function char_to_int(c){
20switch (c){
21case 'I': return 1;
22case 'V': return 5;
23case 'X': return 10;
24case 'L': return 50;
25case 'C': return 100;
26case 'D': return 500;
27case 'M': return 1000;
28default: return -1;
29}
30}
31console.log(roman_to_Int('XXVI'));
32console.log(roman_to_Int('CI'));

1class Solution {
2public:
3    int romanNumber(char n)
4    {
5        switch (n)
6        {
7        case 'I':
8                return (1);
9        case 'V':
10                return (5);
11        case 'X':
12                return (10);
13        case 'L':
14                return (50);
15        case 'C':
16                return (100);
17        case 'D':
18                return (500);
19        case 'M':
20                return (1000);
21        default:
22            return (0);
23            
24        }
25        return (0);
26    }
27    int romanToInt(string s) 
28    {
29        int len = s.size();
30        int ans = romanNumber(s[0]);
31        for(int i=1;i<len;i++)
32        {
33            int prev = romanNumber(s[i-1]);
34            int current = romanNumber(s[i]);
35            if(prev>=current)
36            {
37                ans += current;
38            }
39            else
40            {
41                ans -= prev;
42                current -= prev;
43                ans += current; 
44            }
45        }
46        return ans;
47    }
48};