Design a function to detect whether a given directed graph contains a cycle. The graph will be given as an adjacency list representation. **Function Signature:** `def has_cycle(graph: List[List[int]]) -> bool:` **Constraints:** - The number of vertices in the graph will be between 1 and 10^5. - The number of edges will be between 0 and 10^5. **Example 1:** Input: `graph = [[1], [2], []]` Output: `False` **Example 2:** Input: `graph = [[1], [2], [0]]` Output: `True` (Graph contains a cycle)

``` def has_cycle(graph): visited = [False] * len(graph) rec_stack = [False] * len(graph) def dfs(node): visited[node] = True rec_stack[node] = True for neighbor in graph[node]: if not visited[neighbor]: if dfs(neighbor): return True elif rec_stack[neighbor]: return True rec_stack[node] = False return False for node in range(len(graph)): if not visited[node]: if dfs(node): return True return False ```