LeetCode第12题--整数转罗马数字

用两个数组表示值和罗马，包括其中的特殊情况一一对应，一共13种
注意里面判断要用while循环，因为num减去一个数的时候还会小于上一个判断的数，罗马数字可能会连续重复，比如III

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

    }
};

Python直接使用字典表示，for key,value in hasmap.items()循环键值对要用items

class Solution:
    def intToRoman(self, num: int) -> str:
        hasmap = {1000:'M',900:'CM',500:'D',400:'CD',100:'C',90:'XC',50:'L',40:'XL',10:'X',9:'IX',5:'V',4:'IV',1:'I'}
        ans = ''
        for key,value in hasmap.items():
            while num >= key:
                ans += value
                num -= key
        return ans