Integer to Roman C++ LeetCode

intToRoman.cpp

class Solution {
public:
    string intToRoman(int num) {
        string result = "";
        
        int numerals[7] =      { 1,    5,   10,    50,     100,    500,    1000 };
        char numerals_key[7] = { 'I', 'V',  'X',   'L',    'C',    'D',    'M'};
        
        int remainders[6] =      { 4,    9,     40,     90,      400,     900 };
        char* remainders_key[6] = { "IV", "IX",  "XL",   "XC",    "CD",    "CM"};

        while(num != 0)
        {
            int quotient = int(pow(10, (to_string(num).length() - 1)));
            //cout << num << " / " << quotient << endl;

            int nnum = num / quotient;
            //cout << quotient << " goes into " << num << " " << nnum << " times" << endl;

            num = num % int(pow(10, (to_string(num).length() - 1)));
            //cout << "Remainder: " << num << endl;
            
            int numeral = quotient * nnum;
            //cout << "Numeral: " << numeral << endl;
        
            if(numeral < 4)
            {
                while(numeral > 0)
                {
                    result += 'I';
                    numeral--;
                }
            }
            else
            {
                bool found = false;
                for(int i = 0; i<6;i++)
                {
                    if(numeral == remainders[i])
                    {
                        result += remainders_key[i];
                        found = true;
                    }
                }
                for(int i = 0; i<7;i++)
                {
                    if(numeral == numerals[i])
                    {
                        result += numerals_key[i];
                        found = true;
                    }
                }
                if(!found)
                {
                    //cout << "Not found" << endl;
                    
                    for(int i=6; i>=0;i--)
                    {
                        //cout << numeral << " > " << numerals[i] << endl;
                        if(numeral > numerals[i])
                        {
                            //cout << "YES" << endl;
                            result += numerals_key[i];
                            numeral -= numerals[i];
                            num += numeral;
                            break;
                        }
                    }
                }
            }
        }
        return result;
    }
};

Runtime	Memory Usage
60 ms	31.3 MB

Checks for an exact result match to both the normal set of roman numerals and the remainders set. If there are no matches then it determines what the next closest roman numeral match is that is less than or equal to the number being considered. Then the loop repeats on the remaining amount.