因子算法private static void test(int num) {int a (int) Math.sqrt(num)for (int i 2 i a i++)
因子算法
private static void test(int num) { int a = (int) Math.sqrt(num); for (int i = 2; i < a; i++) { if (num % i == 0) { System.out.println(i); } } }? 