摘要:
Roman numerals are represented by seven different symbols: I, V, X, L, C, D and M. ``` Symbol Value I 1 V 5 X 10 L 50 C 100 D 500 M 1000 ``` For examp 阅读全文
摘要:
Given an integer x, return true if x is a palindrome, and false otherwise. **Example 1:** ``` Input: x = 121 Output: true Explanation: 121 reads as 12 阅读全文