假设正读和反读都相同的字符序列为“回文”，例如，‘abba’和‘abcba’是回文，‘abcde’ 和‘ababab’则不是回文。试写一个算法判别读入的一个以‘@’为结束符的字符序列是否是“回文”。-Assuming a positive reading and anti-reads the same sequence of characters " palindrome" , for example, ' abba'　and ' abcba'　palindrome ' abcde'　and ' ababab'　is not a palindrome. Try to write an algorithm to the discriminant read a ' @'　terminator sequence of characters is a palindrome.