Given a directed acyclic graph with n vertices (0 to n-1) and a list of edges, find the smallest set of vertices from which all nodes are reachable.
Example 1:
Input: n=6, edges=[[0,1],[0,2],[2,5],[3,4],[4,2]] Output: [0,3]
Example 2:
Input: n=5, edges=[[0,1],[2,1],[3,1],[1,4],[2,4]] Output: [0,2,3]
Constraints:
- 2 <= n <= 10^5
- edges[i].length == 2
- The graph is a DAG.