add: Pow(x, n)

README.md

@@ -73,18 +73,18 @@ LeetCode 与 LintCode 解题记录。此为个人练习仓库，代码中对重
 
 - [最后一个单词的长度](src/string/length-of-last-word.js)
 
-  - LeetCode 58. 最后一个单词的长度 https://leetcode-cn.com/problems/length-of-last-word/
-  - LintCode 422. 最后一个单词的长度 https://www.lintcode.com/problem/length-of-last-word/description
+  - LeetCode 58. 最后一个单词的长度 <https://leetcode-cn.com/problems/length-of-last-word/>
+  - LintCode 422. 最后一个单词的长度 <https://www.lintcode.com/problem/length-of-last-word/description>
 
 - [整数转罗马数字](src/string/integer-to-roman.js)
 
-  - LeetCode 12. 整数转罗马数字 https://leetcode-cn.com/problems/integer-to-roman/
-  - LintCode 418. 整数转罗马数字 https://www.lintcode.com/problem/integer-to-roman/description
+  - LeetCode 12. 整数转罗马数字 <https://leetcode-cn.com/problems/integer-to-roman/>
+  - LintCode 418. 整数转罗马数字 <https://www.lintcode.com/problem/integer-to-roman/description>
 
 - [罗马数字转整数](src/string/roman-to-integer.js)
 
-  - LeetCode 13. 罗马数字转整数 https://leetcode-cn.com/problems/roman-to-integer/
-  - LintCode 419. 罗马数字转整数 https://www.lintcode.com/problem/roman-to-integer/description
+  - LeetCode 13. 罗马数字转整数 <https://leetcode-cn.com/problems/roman-to-integer/>
+  - LintCode 419. 罗马数字转整数 <https://www.lintcode.com/problem/roman-to-integer/description>
 
 ## 数组
 
@@ -319,6 +319,11 @@ LeetCode 与 LintCode 解题记录。此为个人练习仓库，代码中对重
   - LeetCode 9. 回文数 <https://leetcode-cn.com/problems/palindrome-number/>
   - LintCode 491. 回文数 <https://www.lintcode.com/problem/palindrome-number/>
 
+- [Pow(x, n)](src/math/powx-n.js)
+
+  - LeetCode 50. Pow(x, n) <https://leetcode-cn.com/problems/powx-n/>
+  - LintCode 428. x的n次幂 <https://www.lintcode.com/problem/powx-n/>
+
 ## 堆
 
 - [超级丑数](src/stack/super-ugly-number.js)【未完成】