Solution: Compilation Order

Explore how to apply topological sorting to solve the compilation order problem by modeling class dependencies as a graph. Understand how to build the graph, identify sources, and use BFS traversal to produce a valid compilation sequence. Learn to detect cycles and evaluate algorithm efficiency to confidently solve dependency-related interview questions.

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Statement
Solution
- Naive approach
- Optimized approach using topological sort

Statement

There are a total of $n$ classes labeled with the English alphabet ( $A$ , $B$ , $C$ , and so on). Some classes are dependent on other classes for compilation. For example, if class $B$ extends class $A$ , then $B$ has a dependency on $A$ . Therefore, $A$ must be compiled before $B$ .

Given a list of the dependency pairs, find the order in which the classes should be compiled.

Constraints:

Class name should be an uppercase character.
$0 \leq$ dependencies.length $\leq 676$
dependencies[i].length $= 2$

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