摘要： 判断String是否为palindrome：Two Pointers(left & right) 同时边扫边check 当前两边的char是否相同 code 判断number是否为palindrome：先reverse original number 变为reversed number ，再判断 o 阅读全文

摘要： StringBuilder objects are like String objects, except that they can be modified. Internally, these objects are treated like variable-length arrays tha 阅读全文