然后第二题暴力过了 import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int left = sc.nextInt(); int right = sc.nextInt(); int time = 0; int[] ints = new int[10]; //避免频繁创建数组 for (int i = left; i <= right; i++) { if (isOk(ints, i)) { time++; } } System.out.println(time); } public static boolean isOk(int[] ints, int num) { int index = 0; while (num != 0) { ints[index++] = num % 10; num /= 10; } return isSumSame(0, 0, ints, 0, index); } private static boolean isSumSame(int sum1, int sum2, int[] ints, int i, int length) { if (i == length) { return sum1 == sum2; } return isSumSame(sum1, sum2 + ints[i], ints, i + 1, length) || isSumSame(sum1 + ints[i], sum2, ints, i + 1, length); } }