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Problem Interview
Figure 1 represents a dependency graph between the modules of a system. The edge indicates the dependency relationship between two modules indicated by the way of the arrow, for example: 1 ? 2 indicates that module 1 is a dependency of module 2 (or the module 2 depends on module 1). In other words, to load module 2 it is necessary to load module 1 first.
Implement an algorithm in C# that returns the correct order of loading all modules of the system.
Figure 1. Dependency graph between the modules of a system.