Problem

Imagine a project with several tasks, each labeled from 0 to numTasks - 1. You have an array of dependencies where dependencies[i] = [a, b] indicates that task b must be completed before task a.

Determine if it is possible to complete all tasks given these constraints.

Examples

canComplete(4, [[2, 0], [1, 0], [3, 1], [3, 2]])
// return true
/* Why? Task 0 must be completed before 1 and 2
Task 1 must be completed before 3
Task 2 must be completed before 3
Valid sequence is 0 -> 1 -> 2 -> 3 or 0 -> 2 -> 1 -> 3 */