Contact Trace Cluster Size

A health team tracks n people, numbered 1 through n, and m recorded contacts. Each contact links two people who met, and contact is mutual. A contact cluster is a maximal set of people all reachable from one another through chains of contacts.

Given a query person q, report how many people belong to q's contact cluster, counting q itself.

Input format

• Line 1: two integers n and m.
• Next m lines: two integers u and v (1-indexed), a recorded contact between and .

Output format

A single integer: the number of people in q's contact cluster.

Constraints

• 1 <= n <= 100000
• 0 <= m <= 200000
• 1 <= u, v, q <= n