Given a string which consists of lowercase or uppercase letters, find the length of the longest palindromes that can be built with those letters.This is case sensitive, for example"Aa"is not con

题目思路很简单，难点在于函数返回值要符合题意要求。用C语言有几个要解决的问题。1.二级指针的初始化和赋值初始化：二维指针初始化分配空间分成两步操作：先分配二维指针的行数再分配每行的数据空间2.C语言整形转字符串.一开始想要使用itoa().提示：implicit declaration of function itoa.原因是itoa()并不在C语言标准