Hello from Carl.
There is a list of packages A, B, C, D, etc. and a list of dependencies:
B -> A(package B depends on successful compilation of A)X -> A, BD -> XF -> B, D
[package a: depend package b]
Class Solution:
def ...This problem asks for a valid build order of packages given dependency relationships. Model each dependency as a directed edge from prerequisite to dependent package, then compute a topological ordering so every package appears after all of its prerequisites. A DFS-based approach can also detect cycles if they exist. In the sample, A must come first, followed by B, then X, then D, and finally F.
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