LeetCode Integer to Roman

最新推荐文章于 2020-06-29 15:21:54 发布

weixin_37806277

最新推荐文章于 2020-06-29 15:21:54 发布

阅读量132

点赞数

CC 4.0 BY-SA版权

本文链接：https://blog.youkuaiyun.com/weixin_37806277/article/details/78714536

本文提供两种将整数转换为罗马数字的Java实现方法。第一种方法通过数组存储罗马数字的基本单位，按千位、百位、十位、个位进行匹配；第二种方法采用递减的方式，遍历预设的数值与符号对照表。

问题网址：https://leetcode.com/problems/integer-to-roman/description/

问题描述：
给定一个整数，将其转换为罗马数字。

输入保证在1到3999的范围内。

LeetCode这道问题并没有给出非常明确的输入输出，似乎显得意义不明

下面给出两种简单解法

public static String intToRoman(int num) {
    String M[] = {"", "M", "MM", "MMM"};
    String C[] = {"", "C", "CC", "CCC", "CD", "D", "DC", "DCC", "DCCC", "CM"};
    String X[] = {"", "X", "XX", "XXX", "XL", "L", "LX", "LXX", "LXXX", "XC"};
    String I[] = {"", "I", "II", "III", "IV", "V", "VI", "VII", "VIII", "IX"};
    return M[num/1000] + C[(num%1000)/100] + X[(num%100)/10] + I[num%10];
}

public class Solution {
    public String intToRoman(int num) {

        int[] values = {1000,900,500,400,100,90,50,40,10,9,5,4,1};
        String[] strs = {"M","CM","D","CD","C","XC","L","XL","X","IX","V","IV","I"};

        StringBuilder sb = new StringBuilder();

        for(int i=0;i<values.length;i++) {
            while(num >= values[i]) {
                num -= values[i];
                sb.append(strs[i]);
            }
        }
        return sb.toString();
    }
}