Topological Sorting in Practice | Dataford Interview Questions

Explain how you would solve a LeetCode-style graph traversal problem that involves topological sorting.

Implement find_order(num_courses, prerequisites), where each pair [course, prerequisite] is a directed edge. Return an ordering containing every course, or [] if dependencies contain a cycle.

Example: find_order(2, [[1, 0]]) returns [0, 1]; find_order(2, [[1, 0], [0, 1]]) returns []. Constraints: 1 <= num_courses <= 10^4, 0 <= len(prerequisites) <= 5 * 10^4.

Constraints

1 <= num_courses <= 10^4
0 <= prerequisites.length <= 5 * 10^4
Each prerequisite has the form [course, prerequisite].
0 <= course, prerequisite < num_courses
course != prerequisite
Any valid topological ordering is accepted.

Function Signature

def find_order(num_courses, prerequisites):

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