用Java編寫模式方法以查找數組中最不經常出現的元素

Question

我有具有類似數據的字符串數組列表 {「this」，「is」，is「，」repeating「}

我需要一個Java代碼，這將使我的元件（一個或多個），其是至少重複

輸出應該是 此= 1 重複= 1

預先感謝

Answer 1

這將做訣竅，這是一個有點長，但也許有一些utils包，做同樣的（還沒有找到一個至今）：

String[] words = {"this", "is", "is", "repeating"}; 

    TreeMap<Integer, List<String>> frequencyMap = new TreeMap<Integer, List<String>>(); 
    for (String word : words) { 
     Integer frequency = 0; 
     for (String word2 : words) { 
      if (word.equals(word2)) { 
       frequency++; 
      } 
     } 

     if (frequencyMap.containsKey(frequency)) { 
      List<String> wordsWithFrequency = frequencyMap.get(frequency); 
      wordsWithFrequency.add(word); 
     } else { 
      List<String> wordsWithFrequency = new ArrayList<String>(); 
      wordsWithFrequency.add(word); 
      frequencyMap.put(frequency, wordsWithFrequency); 
     } 
    } 

    if (frequencyMap.size() > 0) { 
     List<String> leastFrequentWords = frequencyMap.get(frequencyMap.firstKey()); 
     for (String string : leastFrequentWords) { 
      System.out.println(string + " = " + frequencyMap.firstKey()); 
     } 
    } 

此打印出：

this = 1 
repeating = 1