编写一个方法用于验证指定的字符串是否为反转字符,返回true和false。请用递归算法实现
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static void Main(string[] args) { string[] strs = { "cabgfcgfbac", "ab", "abc", "abcca" }; foreach (string str in strs) Console.WriteLine("{0} is {1}", str, method(str)); Console.ReadLine(); } private static bool method(string str) { if (str.Length <= 1) return true; if (str[0] != str[str.Length - 1]) return false; return method(str.Substring(1, str.Length - 2)); }