There is an undirected graph with n nodes. The graph is represented as a 0-indexed 2D integer array graph where graph[u] is an array of nodes that node u is adjacent to.

Return true if and only if the graph is bipartite. A graph is bipartite if we can split its nodes into two independent sets A and B such that every edge connects a node in A to one in B.

Example 1:

Input:
4
1 3
0 2
1 3
0 2
Output: true

Example 2:

Input:
4
1 2 3
0 2
0 1 3
0 2
Output: false

Constraints:

• graph.length == n
• 1 ≤ n ≤ 100
• 0 ≤ graph[u].length < n
• 0 ≤ graph[u][i] ≤ n-1
• No self-loops, no repeated edges

Input format: First line: n. Then n lines, each with space-separated neighbors (empty line for isolated node).

Output format: true or false.