求1000以内的回文数
//回文数
public static void fun4(){
for (int i = 0; i < 10; i++) {
System.out.println(i);
}
for (int i = 10; i < 100; i++) {
int d = i%100/10;
int e = i%10;
if (e == d) {
System.out.println(i);
}
}
for (int i = 100; i <1000; i++) {
int c = i % 1000/100;// c= 3
int d = i%100/10;
int e = i%10;
if (e == c) {
System.out.println(i);
}
}
}