摘要： Implement regular expression matching with support for '.' and '*'.'.' Matches any single character. '*' Matches zero or more of the preceding element. The matching should cover the entire input stri... 阅读全文

摘要： Determine whether an integer is a palindrome. Do this without extra space.Some hints:Could negative integers be palindromes? (ie, -1)If you are thinking of converting the integer to string, note the r... 阅读全文

摘要： Implement atoi to convert a string to an integer.Hint: Carefully consider all possible input cases. If you want a challenge, please do not see below and ask yourself what are the possible input cases.... 阅读全文