题目

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用到的知识

集合排序

  1. //对数字进行排序
  2. List<Integer> nums = Arrays.asList(3,1,5,2,9,8,4,10,6,7);
  3. nums.sort(Comparator.reverseOrder()); //reverseOrder倒序
  4. System.err.println("倒序:"+nums);
  6. nums.sort(Comparator.naturalOrder()); //naturalOrder自然排序即：正序
  7. System.err.println("正序:"+nums);

解题代码

  1. class Solution {
  2.     public String originalDigits(String s) {
  3.         /**
  4.          * 0: zero  z
  5.          * 1: one
  6.          * 2: two  w
  7.          * 3: three
  8.          * 4: four  u
  9.          * 5: five
  10.          * 6: six   x
  11.          * 7: seven
  12.          * 8: eight   g
  13.          * 9: nine
  14.          *
  15.          * g,u, w,x,z
  16.          *
  17.          * zero,two,four, six ,eight,
  18.          *
  19.          * one,three,five,seven,
  20.          * r,s,f,o
  21.          */
  22.         char[] chars = s.toCharArray();
  23.         Map<Character,Integer> map = new HashMap<>();
  24.         for (char c: chars ) {
  25.             map.put(c,map.getOrDefault(c,0) + 1);
  26.         }
  28.         //除去只出现一次的数字
  29.         List<Integer> l = new ArrayList<>();
  30.         if(map.containsKey('z')) {
  31.             addList('z',map,0,l,"zero");
  32.         }
  33.         if(map.containsKey('w')) {
  34.             addList('w',map,2,l,"two");
  35.         }
  36.         if(map.containsKey('u')) {
  37.             addList('u',map,4,l,"four");
  38.         }
  39.         if(map.containsKey('x')) {
  40.             addList('x',map,6,l,"six");
  41.         }
  42.         if(map.containsKey('g')) {
  43.             addList('g',map,8,l,"eight");
  44.         }
  47.         /**
  48.          * one,three,five,seven,
  49.          *          * r,s,f,o
  50.          */
  52.         //排除上述 数字，除去只出现一次的数字
  53.         if(map.containsKey('o')) {
  54.             addList('o',map,1,l,"one");
  55.         }
  56.         if(map.containsKey('r')) {
  57.             addList('r',map,3,l,"three");
  58.         }
  59.         if(map.containsKey('f')) {
  60.             addList('f',map,5,l,"five");
  61.         }
  62.         if(map.containsKey('s')) {
  63.             addList('s',map,7,l,"seven");
  64.         }
  66.         //nine 统计i或者e的个数
  67.         if(map.containsKey('i')) {
  68.             addList('i',map,9,l,"nine");
  69.         }
  71.         l.sort(Comparator.naturalOrder());
  72.         String result = l.stream().map( t -> String.valueOf(t)).collect(Collectors.joining(""));
  74.         return result;
  75.     }
  77.     public void addList(char c,Map<Character,Integer> map,int num, List<Integer> l,String s) {
  79.         int len = map.get(c); //统计出现次数
  80.         for(int i = 0; i < len ; i++ ) {
  81.             l.add(num); //加入集合
  82.         }
  83.         char[] chars = s.toCharArray(); 
  84.         for (int i = 0; i < chars.length; i++) { 
  85.             int value = map.get(chars[i])- len;
  86.             if(value == 0) { //为0删除char
  87.                 map.remove(chars[i]);
  88.             } else {
  89.                 map.put(chars[i], value ) ; //更新字符出现次数
  90.             }
  92.         }
  93.     }
  94. }