Course Schedule

You are given numCourses courses labeled 0 to numCourses - 1 and a list of prerequisite pairs. Each pair [a, b] means you must take course b before course a.

Return True if it is possible to finish all courses, or False if a cycle makes it impossible.

---

Example 1

Input: numCourses = 2, prerequisites = [[1, 0]]
Output: True
Explanation: Take course 0 first, then course 1.

Example 2

Input: numCourses = 2, prerequisites = [[1, 0], [0, 1]]
Output: False
Explanation: Course 0 requires course 1, and course 1 requires course 0 - a cycle.

Example 3

Input: numCourses = 4, prerequisites = [[1, 0], [2, 1], [3, 2]]
Output: True
Explanation: Linear chain 0 -> 1 -> 2 -> 3 with no cycle.

---

Constraints

• 1 <= numCourses <= 2000
• 0 <= prerequisites.length <= 5000
• prerequisites[i].length == 2
• 0 <= a, b < numCourses
• All prerequisite pairs are unique