Check Path Presence

Problem Overview

• Determine if an undirected graph has a direct path 1→2→…→N, visiting all vertices in increasing order.
• Input: N vertices and M edges via arrays A and B; Output: return 1 if such an ordered path exists, else 0.
• Domain: graph theory validation of ordered connectivity, relevant to network routing or workflow sequences.
• This Microsoft interviews problem is a classic coding interview and interview question.