the getMax function in binary search tree may not work correctly about c HOT 8 CLOSED

There is an active pull-request in C++ for this file TheAlgorithms/C-Plus-Plus#891
It would be very helpful if you can weigh in on both of them.
Thank you for pointing out the possible error.

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@liushubin-gitHub it would be great if you can take a look here as well. Thank you.
(PS: The static code checks are not so stringent here as C is a more primitive language than C++ 😄 )

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@kvedala @bayegy LGTM

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@kvedala
Hi, I am not sure if this will answer your question.
But I think the implementation of function findMaxInLeftST() in binary_search_tree.cpp is correct. it works fine.

I did not read the "active pull-request" thoroughly, but I have tested the function Remove() in binary_search_tree.cpp. It did not work in some cases. For example, If I want to delete 50 from the tree mentioned above, it throws segmentation fault error. I think the possible
correct implementation of Remove() could be:

void Remove(node **p, int x) {
    if ((*p) == NULL) {
        return;
    }
    if ((*p)->val == x) {
        if ((*p)->right == NULL && (*p)->left == NULL) {
            (*p) = NULL;
        } else if ((*p)->right == NULL) {
            (*p) = (*p)->left;
        } else if ((*p)->left == NULL) {
            (*p) = (*p)->right;
        } else {
            int y = findMaxInLeftST((*p)->left);
            (*p)->val = y;
            Remove(&((*p)->left), y);
        }
    } else if (x < (*p)->val) {
        Remove(&((*p)->left), x);
    } else {
        Remove(&((*p)->right), x);
    }
}

If you want to delete a node from a tree, just use:

Remove(&root, x);

This implementation have been tested worked in various situation. Also, correct me if I was wrong, please.

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LGTM.+1
i have fixed it.segment fault is because null pointer check missing

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Thank you, @liushubin-gitHub
@bayegy please feel free to create a pull-request with your suggested fixes. Along with the fixes, please update the code with structure and formatting as the other files like this in the repo. Thank you 😄

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@bayegy can you review the PR #579 Thanks.

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@kvedala yes, I have reviewed the PR. looks good to me

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