1.定義 Map<String, Integer> map = new HashMap<String,Integer>(); 2.判斷map中是否存在某個鍵的值: if(map.get(s)==null) 3.給map中某個鍵賦值: map.put(s, value); 4.map的遍歷: 法一: Set<String> key = map.keySet(); for(String k:key) { System.out.println(k+":"+map.get(k)); } 法二: Iterator<String> it = key.iterator(); while(it.hasNext()) { String s = it.next(); System.out.println(s+":"+map.get(s)); }
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