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Tree with parents

 
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Hi,
I have a tree structure that uses a list of nodes for the children, along with a reference to the parent.
I would like to be able to extract a node incorporating the data from the ancestors of a node.
But, I don't know how to call a member of the generic class.





I have an alternative solution where the generic class contains a reference to a tree node, and can access the parent, so the generic class can construct the summary.
In the alternative solution, I don't get the expected result of "Beginning of the week", 6. The output is "week", 3.

 
John Vorwald
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The alternative solution had a error in the incorporateParent member. The correction is below.
But, I'd still prefer to use the first alternative, to have the tree/node class manage incorporating ancestors data, instead of passing the tree node to the generic class.

 
John Vorwald
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I dug a little deeper into how the treenode class could be modified to manage the incorporating of ancestors. One approach to allow a generic function to call a specific member function is to make the generic extend an interface that defines the function.

The following code is an example of a tree that is able to incorporate data from ancestor nodes. It produces the result "Beginning of the week", 6, which is the desired result.

 
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