题解 | 2024_田忌赛马_1730全排列暴力枚举

import java.util.Arrays;
import java.util.LinkedList;
import java.util.List;
import java.util.Scanner;

public class Main {
    private static int[] nums;
    private static List<Integer> list = new LinkedList<>();
    private static boolean[] used;

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt(), x = sc.nextInt();
        nums = new int[n];
        used = new boolean[n];
        for (int i = 0; i < n; i++) nums[i] = sc.nextInt();
        backtrack(n, x);
        sc.close();
    }

    private static void backtrack(int n, int x) {
        if (list.size() == n) {
            int count = 0;
            for (int i = 0; i < n; i++) if (list.get(i) - nums[i] >= x) count++;
            if (count > n / 2) {
                list.forEach(o -> System.out.print(o + " "));
                System.out.println();
            }
            return;
        }
        for (int i = 0; i < n; i++) {
            if (used[i]) continue;
            used[i] = true;
            list.add(i + 1);
            backtrack(n, x);
            list.remove(list.size() - 1);
            used[i] = false;
        }
    }
}