Integer to Roman.cpp

// Runtime: 3 ms (Top 96.82%) | Memory: 6 MB (Top 78.88%)
class Solution {
public:
    string intToRoman(int num) {
        string ans="";
        while(num>=1000){
            ans += 'M';
            num -= 1000;
        }
        while(num>=900){
            ans += "CM";
            num -= 900;
        }
        while(num>=500){
            ans += 'D';
            num -= 500;
        }
        while(num>=400){
            ans += "CD";
            num -= 400;
        }
        while(num>=100){
            ans += 'C';
            num -= 100;
        }
        while(num>=90){
            ans += "XC";
            num -= 90;
        }
        while(num>=50){
            ans += 'L';
            num -= 50;
        }
        while(num>=40){
            ans += "XL";
            num -= 40;
        }
        while(num>=10){
            ans += 'X';
            num -= 10;
        }
        while(num>=9){
            ans += "IX";
            num -= 9;
        }
        while(num>=5){
            ans += 'V';
            num -= 5;
        }
        while(num>=4){
            ans += "IV";
            num -= 4;
        }
        while(num>0){
            ans += 'I';
            num -= 1;
        }
        return ans;
    }
};