比起dp[21][21][21]来少存了5000个数，不知道为啥还是会爆内存

import java.util.Scanner;

public class Main {
    //存变化的2470个数字
    static int[] newDp = new int[2491];
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = 1;
        for (int i = 0; i <= 20; i++) {
            newDp[i] = n;
            n *= 2;
        }
        w();
        int[] nums = new int[3];
        String[] arr;
        while (true) {
            //字符串判断
            arr = sc.nextLine().split(" ");
            if (arr[0].equals("-1") && arr[1].equals("-1") && arr[2].equals("-1")) {
                break;
            }

            //判断长度大的数字是正数还是负数，并且将字符串中的数字放到整数数组中
            for (int i = 0; i < arr.length; i++) {
                if (arr[i].length() > 2) {
                    if (arr[i].charAt(0) == '-') {
                        nums[i] = -1;
                    } else {
                        nums[i] = 21;
                    }
                } else {
                    nums[i] = Integer.parseInt(arr[i]);
                }
            }

            //判断整数数组是否满足规则一
            for (int i = 0; i < nums.length; i++) {
                if (nums[i] <= 0) {
                    nums[0] = nums[1] = nums[2] = 0;
                    break;
                }
            }

            //判断是否符合规则二
            for (int i = 0; i < nums.length; i++) {
                if (nums[i] > 20) {
                    nums[0] = nums[1] = nums[2] = 20;
                }
            }
            
            System.out.println("w(" + arr[0] + ", " + arr[1] + ", " + arr[2] + ")" + " = " + newDp[getSub(nums[0], nums[1], nums[2])]);
        }
    }

    private static int getSub(int a, int b, int c) {
        if (a > b && a > c && b != 0 && c != 0) {
            int num = 20;
            for (int i = 1; i < a - 1; i++) {
                num += i * i;
            }
            num += (b - 1) * (a - 1) + c;
            return num;
        } else if (b == 0 || c == 0) {
            return 0;
        } else {
            return a;
        }
    }

    private static void w() {
        for (int i = 21; i < newDp.length; i++) {
            for (int a = 2; a <= 20; a++) {
                for (int b = 1; b < a; b++) {
                    for (int c = 1; c < a; c++) {
                        if (getSub(a, b, c) == i) {
                            newDp[i] = newDp[getSub(a - 1, b, c)] + newDp[getSub(a - 1, b - 1, c)] + newDp[getSub(a - 1, b, c - 1)] - newDp[getSub(a - 1, b - 1, c - 1)];
                        }
                    }
                }
            }
        }
    }
}