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???????????O(n + k log k)???n???????k??????k???????????????????O(n log n)?

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import java.util.ArrayList;import java.util.Collections;import java.util.HashMap;import java.util.Map;import java.util.Comparator;public class Solution {    private static List
   
     topKFrequent(int[] nums, int k) {        Map
    
      map = new HashMap<>();        for (int num : nums) {            if (map.containsKey(num)) {                map.put(num, map.get(num) + 1);            } else {                map.put(num, 1);            }        }        List
     
      
       > entryList = new ArrayList<>(map.entrySet());        Collections.sort(entryList, new Comparator
       
        
         >() { @Override public int compare(Map.Entry
         
           item1, Map.Entry
          
            item2) { return item2.getValue() - item1.getValue(); } }); ArrayList
           
             result = new ArrayList<>(); int j = 0; for (Map.Entry
            
              entry : entryList) { if (j >= k) { break; } result.add(entry.getKey()); j++; } return result; } private static final Comparator
             
              
               > mapComparator = new Comparator
               
                
                 >() { @Override public int compare(Map.Entry
                 
                   item1, Map.Entry
                  
                    item2) { return item2.getValue() - item1.getValue(); } };}
                  
                 
                
               
              
             
            
           
          
         
        
       
      
     
    
   

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