Every tree is a graph, but not every graph is tree. Because graphs have so much more optionality with their edges, graphs can get extremely complicated. Make sure that you master this critical data structures and its accompanying algorithms, particularly with traversal.
If you need additional support taking those skills and actually applying them, take Alvin's complete data structures and algorithms course on Structy. You can try out the concepts yourself in their interactive code editor and learn advanced DSA patterns like stack exhaustive recursion.
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