Update README.md

Author: zewenw

solution/README.md

@@ -22,8 +22,8 @@
 |  0009  |  [回文数](/solution/0000-0099/0009.Palindrome%20Number/README.md)  |  `数学`  |  简单  |   done |
 |  0010  |  [正则表达式匹配](/solution/0000-0099/0010.Regular%20Expression%20Matching/README.md)  |  `递归`,`字符串`,`动态规划`  |  困难  |    |
 |  0011  |  [盛最多水的容器](/solution/0000-0099/0011.Container%20With%20Most%20Water/README.md)  |  `贪心`,`数组`,`双指针`  |  中等  | done   |
-|  0012  |  [整数转罗马数字](/solution/0000-0099/0012.Integer%20to%20Roman/README.md)  |  `哈希表`,`数学`,`字符串`  |  中等  |    |
-|  0013  |  [罗马数字转整数](/solution/0000-0099/0013.Roman%20to%20Integer/README.md)  |  `哈希表`,`数学`,`字符串`  |  简单  |    |
+|  0012  |  [整数转罗马数字](/solution/0000-0099/0012.Integer%20to%20Roman/README.md)  |  `哈希表`,`数学`,`字符串`  |  中等  |  done  |
+|  0013  |  [罗马数字转整数](/solution/0000-0099/0013.Roman%20to%20Integer/README.md)  |  `哈希表`,`数学`,`字符串`  |  简单  |  done  |
 |  0014  |  [最长公共前缀](/solution/0000-0099/0014.Longest%20Common%20Prefix/README.md)  |  `字典树`,`字符串`  |  简单  |    |
 |  0015  |  [三数之和](/solution/0000-0099/0015.3Sum/README.md)  |  `数组`,`双指针`,`排序`  |  中等  |    |
 |  0016  |  [最接近的三数之和](/solution/0000-0099/0016.3Sum%20Closest/README.md)  |  `数组`,`双指针`,`排序`  |  中等  |    |