import java.util.*;
public class Zuoye5 {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.println("请输入一串字符串");
String n =input.next();
int i = 0;
int j= n.length();
while(i<=(j/2)-1&&n.charAt(i)==n.charAt(j-i-1))
i++;
if(i==j/2){
System.out.printf("此字符串是回文!\n");
}
else
System.out.printf("此字符串不是回文!\n");
}
}