c++实现整数转罗马数字

#include 
class Solution {
public:
    string intToRoman(int num) {
        string arr1[]={"M","CM","D","CD","C","XC","L","XL","X","IX","V","IV","I"};
        int nums[]={1000,900,500,400,100,90,50,40,10,9,5,4,1};
        string arr;
        for(int i=0;i<13;i++)
        {
            while(num>=nums[i])
            {
                arr+=arr1[i];
                num-=nums[i];
            }
        }
        return arr;
    }
};