Super-simple Java, beats 100% despite poor algorithm  :-)
Very easy, but worst case, this is O(n^2), which is bad.  However, it beats 100%!  We need bigger/uglier test cases. ```     public TreeNode subtreeWithAllDeepe
Very easy, but worst case, this is O(n^2), which is bad.  However, it beats 100%!  We need bigger/uglier test cases.
```
    public TreeNode subtreeWithAllDeepest(TreeNode root) {
        if( root==null ) return root;
        int L=height(root.left);
        int R=height(root.right);
        if( L==R ) return root;
        if( L<R ) return subtreeWithAllDeepest( root.right );
        else return subtreeWithAllDeepest( root.left );
    }
    
    private static int height( TreeNode node )
    {
        if( node==null ) return 0;
        return 1+Math.max( height(node.left), height(node.right) );
    }
```

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