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Graph Data Structure?

 
Greenhorn
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where the Integer key represents the vertex and the LinkedList contains all the other vertexes it points to.

How can I go about using an ArrayList to represent the vertex and the list of vertexes is points to?
 
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You shouldn't care about the concrete type at all. Declare the variable like this:
Then when you add a new link, you can get the neighbor vertices like this:
 
Sheriff
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Stephan van Hulst wrote:


Fixed.
 
Stephan van Hulst
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Hah, I keep forgetting to be lazy.
 
Rob Spoor
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I just wish they had overloaded comuteIfAbsent to not only take a Function<Key, Value> but also a Supplier<Value>. That would have allowed ArrayList::new instead of k -> new ArrayList<>().
 
Stephan van Hulst
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I feel ya. One thing that often annoys me is when I use compute() to replace a value in the map, based solely the old value. It's really the same issue, it would be nice if they added
 
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