public class Main { public static void main(String[] args) { for (int i = 0; i<= 256; i++) { String s = String.valueOf(i * i); int j=0; int k= s.length()-1; while (j<=k){ if (s.charAt(j)==s.charAt(k)){ j++; k--; }else break; } if (j>k) System.out.println(i); } } }