Scanner in = new Scanner(System.in); int[] arr ={0,1,5,6,25,76,376,625,9376}; int b = Integer.valueOf(in.nextLine() ); int ct=0; for(int i=0;i<arr.length;i++){ if(b>=arr[i]){ ct ++; } } System.out.println(ct); 根据题目规则枚举出来就可以了 static boolean isMatch(int i){ String sq = i*i+""; String s...