如何向Map中的Set添加值？ [英] How do I add values to a Set inside a Map?

问题描述

我有这个地图 Map< String，Set< Integer>> myMap; ，现在我需要与它进行交互，我该怎么做？

I have this map Map<String, Set<Integer>> myMap;, now I need to interact with it, how do I do it?

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键是：苹果，橙色，葡萄等。 br>
每个集合将包含随机数： 1-9

Keys are: "apple", "orange", "grape", etc.
Each set will contain random numbers: 1-9

我需要创建一个Map（HashMap或TreeMap），有字符串用于键值和值的值。我需要返回给定一个键。我还需要能够根据一个键填充多个数字的每个集合。不知道如何解决这个问题。任何想法？

I need to create a Map (HashMap or TreeMap) that has Strings for keys and sets for the values. I need to return the set given a key. I also need to be able to fill each set with multiple numbers based on a key. Not sure how to approach this problem. Any thoughts?

推荐答案

如果我理解正确，不难。

Not difficult if I understand correctly.

Map<String, Set<Integer>> reqdMap = new HashMap<String, Set<Integer>>();

//Form the set corresponding to apple.
Set<Integer> appleSet = new HashSet<Integer>();
appleSet.add(1);
...


reqdMap.put("apple", appleSet);

//To Retrieve
appleSet = reqdMap.get("apple");

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