[Leetcode] Integer to Roman

數字轉羅馬文字，4 & 9 有特例

，除 千 百 十 及餘 取係數出來，如果係數== 9 or 4 就固定某個roman number，不是就 repeat 係數/5的次數 及 repeate 係數% 5的次數，全部加起來就是了

 1 public string IntToRoman(int num)
 2         {
 3             string result = string.Empty;
 4             //千位
 5             var thun = num / 1000;
 6             //百位
 7             var hun = (num = (num - (thun * 1000))) / 100;
 8             //十位
 9             var ten = (num = (num - (hun * 100))) / 10;
10             //個位
11             var remain = num % 10;
12 
13             result += string.Join("", Enumerable.Repeat("M", thun));
14 
15             if (hun == 9)
16                 result += "CM";
17             else if (hun == 4)
18                 result += "CD";
19             else
20             {
21                 //500的重複
22                 result += string.Join("", Enumerable.Repeat("D", hun / 5));
23                 //小於500的重複
24                 result += string.Join("", Enumerable.Repeat("C", hun % 5));
25             }
26 
27             if (ten == 9)
28                 result += "XC";
29             else if (ten == 4)
30                 result += "XL";
31             else
32             {
33                 //50的重複
34                 result += string.Join("", Enumerable.Repeat("L", ten / 5));
35                 //小於50的重複
36                 result += string.Join("", Enumerable.Repeat("X", ten % 5));
37             }
38 
39             if (remain == 9)
40                 result += "IX";
41             else if (remain == 4)
42                 result += "IV";
43             else
44             {
45                 //5的重複
46                 result += string.Join("", Enumerable.Repeat("V", remain / 5));
47                 //小於5的重複
48                 result += string.Join("", Enumerable.Repeat("I", remain % 5));
49             }
50 
51             return result;
52         }

标签：Repeat,Join,string,Roman,num,result,Integer,Enumerable,Leetcode
来源： https://www.cnblogs.com/seako/p/10937142.html