LeetCode - Refresh - Roman to Integer

 1 class Solution {
 2 public:
 3     int romanToInt(string s) {
 4         int len = s.size(), result = 0;
 5         for (int i = 0; i < len; i++) {
 6             switch(s[i]) {
 7                 case 'M':
 8                     result += 1000;
 9                     break;
10                 case 'D':
11                     result += 500;
12                     break;
13                 case 'C':
14                     if (i < len-1 && s[i+1] == 'M') {
15                         result += 900;
16                         i++;
17                     } else if (i < len-1 && s[i+1] == 'D') {
18                         result += 400;
19                         i++;
20                     } else {
21                         result += 100;
22                     }
23                     break;
24                 case 'L':
25                     result += 50;
26                     break;
27                 case 'X':
28                     if (i < len-1 && s[i+1] == 'C') {
29                         result += 90;
30                         i++;
31                     } else if (i < len-1 && s[i+1] == 'L') {
32                         result += 40;
33                         i++;
34                     } else {
35                         result += 10;
36                     }
37                     break;
38                 case 'V':
39                     result += 5;
40                     break;
41                 case 'I':
42                     if (i < len-1 && s[i+1] == 'X') {
43                         result += 9;
44                         i++;
45                     } else if (i < len-1 && s[i+1] == 'V') {
46                         result += 4;
47                         i++;
48                     } else result += 1;
49                     break;
50             }
51         }
52         return result;
53     }
54 };
posted on 2015-03-23 10:28 keepshuatishuati 阅读(105) 评论(0) 编辑收藏举报