2829303132

import java.util.*;

class Solution {
    public int[] topKFrequent(int[] nums, int k) {
        Map<Integer, Integer> freq = new HashMap<>();
        for (int num : nums)
            freq.put(num, freq.getOrDefault(num, 0) + 1);

        PriorityQueue<Map.Entry<Integer, Integer>> pq =
            new PriorityQueue<>(Comparator.comparingInt(Map.Entry::getValue));

        for (Map.Entry<Integer, Integer> e : freq.entrySet()) {
            pq.add(e);
            if (pq.size() > k) pq.poll();
        }

        int[] result = new int[k];
        int i = 0;
        while (!pq.isEmpty()) result[i++] = pq.poll().getKey();
        return result;
    }
}

public class Main {
    public static void main(String[] args) {
        Solution obj = new Solution();
        int[] nums = {1, 1, 1, 2, 2, 3};
        int k = 2;
        System.out.println(Arrays.toString(obj.topKFrequent(nums, k)));
    }
}

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import heapq
from collections import Counter

class Solution:
    def topKFrequent(self, nums, k):
        freq = Counter(nums)
        return [num for num, _ in heapq.nlargest(k, freq.items(), key=lambda x: x[1])]


if __name__ == "__main__":
    obj = Solution()
    print(obj.topKFrequent([1, 1, 1, 2, 2, 3], 2))

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class Solution {
    topKFrequent(nums, k) {
        const freq = new Map();
        for (const num of nums)
            freq.set(num, (freq.get(num) || 0) + 1);

        const sorted = Array.from(freq.entries()).sort((a, b) => b[1] - a[1]);
        return sorted.slice(0, k).map(([num]) => num);
    }
}

const obj = new Solution();
console.log(obj.topKFrequent([1, 1, 1, 2, 2, 3], 2));

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using System;
using System.Collections.Generic;
using System.Linq;

class Solution
{
    public IList<int> TopKFrequent(int[] nums, int k)
    {
        var freq = nums.GroupBy(x => x).ToDictionary(g => g.Key, g => g.Count());
        var pq = new PriorityQueue<int, int>();

        foreach (var kv in freq)
        {
            pq.Enqueue(kv.Key, kv.Value);
            if (pq.Count > k) pq.Dequeue();
        }

        return pq.UnorderedItems.Select(x => x.Element).ToList();
    }
}

class Program
{
    static void Main()
    {
        Solution obj = new Solution();
        int[] nums = { 1, 1, 1, 2, 2, 3 };
        int k = 2;
        Console.WriteLine(string.Join(" ", obj.TopKFrequent(nums, k)));
    }
}

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