12. Integer to Roman

class Solution {
public:
    string intToRoman(int num) {
        
        string result;
        
        while(num){
            
            while(num >= 1000){
                result += "M";
                num -= 1000;
            }
            while(num >= 500){
              if(num >= 900){
                    result += "CM";
                    num -= 900;
                    break;
                }    
                result += "D";
                num -= 500;
            }
            while(num >= 100){
                if(num >= 400){
                    result += "CD";
                    num -= 400;
                    break;
                }    
                result += "C";
                num -= 100;
            }
            while(num >= 50){
                if(num >= 90){
                    result += "XC";
                    num -= 90;
                    break;
                }    
                result += "L";
                num -= 50;
            }
            while(num >= 10){
                if(num >= 40){
                    result += "XL";
                    num -= 40;
                    break;
                }    
                result += "X";
                num -= 10;
            }
            while(num >= 5){
                    if(num >= 9){
                    result += "IX";
                    num -= 9;
                    break;
                }    
                result += "V";
                num -= 5;
            }
            while(num >= 1){
                if(num >= 4){
                    result += "IV";
                    num -= 4;
                    break;
                }    
                result += "I";
                num -= 1;
            }
        }
        return result;
    }
};