Shortest Path in Review Graph

Problem

Given an undirected graph with n nodes labeled 0 to n - 1, an edge list edges, a starting node start, and a target node target, return the length of the shortest path from start to target. If no path exists, return -1. Implement an algorithm that works efficiently for large sparse graphs.

Constraints

• 1 <= n <= 10^5
• 0 <= edges.length <= 2 * 10^5
• edges[i].length == 2
• 0 <= edges[i][0], edges[i][1] < n
• 0 <= start, target < n
• The graph may be disconnected and may contain duplicate edges