Help on the list into question

map There are four string array

s1 = {0,1}

s2 = {0,2}

s3 = {1,1}

s4 = {1,2}

list = {s1, s2, s3, s4}

now want to list the string in the first element of the array into the same map the key value , the second element of the array on the string to form a new array of values ​​as a value .

The resulting map is

map = {key = 0 value = {1,2}, key = 1 value = {1,2}}
hope god more help.



------ Solution ------------------------------------ --------

  	public static void testMap() {
  
  		List<String[]> list = createDatas();
  		Map<String, List<String>> map = new HashMap<String, List<String>>();
  		for (String[] arr : list) {
  			if (2 < arr.length) {
  				throw new IllegalArgumentException("out of index");
  			}
  			String a = arr[0];
  			String b = arr[1];
  			if (!map.containsKey(a)) {
  				List<String> tmpList = new ArrayList<String>();
  				tmpList.add(b);
  				map.put(a, tmpList);
  			} else {
  				map.get(a).add(b);
  			}
  		}
  
  		Iterator<Entry<String, List<String>>> it = map.entrySet().iterator();
  		while (it.hasNext()) {
  			Entry<String, List<String>> entry = it.next();
  			System.out.println(entry);
  		}
  		// ========= output=========
  		// 1=[1, 2, 2, 2]
  		// 0=[1, 2]
  
  	}
  
  	private static List<String[]> createDatas() {
  		String[] s1 = { "0", "1" };
  
  		String[] s2 = { "0", "2" };
  
  		String[] s3 = { "1", "1" };
  
  		String[] s4 = { "1", "2" };
  		String[] s5 = { "1", "2" };
  		String[] s6 = { "1", "2" };
  		List<String[]> list = new ArrayList<String[]>();
  		list.add(s1);
  		list.add(s2);
  		list.add(s3);
  		list.add(s4);
  		list.add(s5);
  		list.add(s6);
  		return list;
  	}
  

------ For reference only ------------------------ ---------------


brother, you are given the code of Java it ? Inside the IDE to write your code above is not being given ? First good tidy your code, and then sent to the questions.
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brother, you are given the code of Java it ? Inside the IDE to write your code above does not   
  
  
  
error ? First good tidy your code, and then sent to the questions. [ /   
quote]   
  
  
The actual algorithm is much more complicated than I, for example , I just use a simple example , let us think about how to help me achieve .  
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2 Floor Hello , thank you for your reply , but I have a question .

I try your method

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2 floor is right, the key issue is to use a list mounted behind the string, thank you.