1129 - Shortest Path with Alternating Colors.

Medium

You are given an integer n, the number of nodes in a directed graph where the nodes are labeled from 0 to n - 1. Each edge is red or blue in this graph, and there could be self-edges and parallel edges.

You are given two arrays redEdges and blueEdges where:

• <code>redEdgesi = a_i, b_i</code> indicates that there is a directed red edge from node <code>a_i</code> to node <code>b_i</code> in the graph, and

• <code>blueEdgesj = u_j, v_j</code> indicates that there is a directed blue edge from node <code>u_j</code> to node <code>v_j</code> in the graph.

Return an array answer of length n, where each answer[x] is the length of the shortest path from node 0 to node x such that the edge colors alternate along the path, or -1 if such a path does not exist.

Example 1:

Input: n = 3, redEdges = [0,1,1,2], blueEdges = []

Output: 0,1,-1

Example 2:

Input: n = 3, redEdges = [0,1], blueEdges = [2,1]

Output: 0,1,-1

Constraints:

• 1 <= n <= 100

• 0 <= redEdges.length, blueEdges.length <= 400

• redEdges[i].length == blueEdges[j].length == 2

• <code>0 <= a_i, b_i, u_j, v_j< n</code>