查找数组中频繁的数字序列

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class FrequentNumberSequence {
    public static List<List<Integer>> findFrequentNumberSequence(int[] nums) {
        Map<Integer, Integer> countMap = new HashMap<>();
        int maxCount = 0;

        // 统计每个数字出现的次数
        for (int num : nums) {
            countMap.put(num, countMap.getOrDefault(num, 0) + 1);
            maxCount = Math.max(maxCount, countMap.get(num));
        }

        List<List<Integer>> frequentSequences = new ArrayList<>();

        // 找出出现次数最多的数字序列
        for (Map.Entry<Integer, Integer> entry : countMap.entrySet()) {
            if (entry.getValue() == maxCount) {
                List<Integer> sequence = new ArrayList<>();
                sequence.add(entry.getKey());
                frequentSequences.add(sequence);
            }
        }

        return frequentSequences;
    }

    public static void main(String[] args) {
        int[] nums = {1, 2, 3, 2, 1, 3, 4, 5, 4, 5, 4, 4};
        List<List<Integer>> frequentSequences = findFrequentNumberSequence(nums);

        System.out.println("Frequent Number Sequences:");
        for (List<Integer> sequence : frequentSequences) {
            System.out.println(sequence);
        }
    }
}