Command Relay Hub Locator

A field team maintains a communications network of n outposts, numbered 1 through n. The network was built as a star: exactly one outpost — the hub — has a direct radio link to every other outpost, and there are no other links in the network. In total there are exactly n - 1 links.

You are given the n - 1 links in some order, each listed as an unordered pair of outpost labels; the two endpoints of a link may appear in either order, and the links themselves may be listed in any order. Determine the label of the hub outpost — the one outpost that appears in every single link.

Input format

The first line contains a single integer n. Each of the next n - 1 lines contains two integers u and v — the labels of the two outposts joined by that link.

Output format

Print a single integer: the label of the hub outpost.

Constraints

• 3 <= n <= 100000
• 1 <= u, v <= n, and u != v for every link
• The given links form a valid star network: one hub outpost directly connected to all n - 1 other outposts, and no other links.

3
1 2
2 3

2

5
1 5
2 5
3 5
4 5

5