1021 Deepest Root

Statement

Metadata

• 作者: CHEN, Yue
• 单位: 浙江大学
• 代码长度限制: 16 KB
• 时间限制: 2000 ms
• 内存限制: 64 MB

A graph which is connected and acyclic can be considered a tree. The height of the tree depends on the selected root. Now you are supposed to find the root that results in a highest tree. Such a root is called the deepest root.

Input Specification

Each input file contains one test case. For each case, the first line contains a positive integer () which is the number of nodes, and hence the nodes are numbered from 1 to . Then lines follow, each describes an edge by given the two adjacent nodes' numbers.

Output Specification

For each test case, print each of the deepest roots in a line. If such a root is not unique, print them in increasing order of their numbers. In case that the given graph is not a tree, print Error: K components where K is the number of connected components in the graph.

Sample Input 1

5
1 2
1 3
1 4
2 5

Sample Output 1

3
4
5

Sample Input 2

5
1 3
1 4
2 5
3 4

Sample Output 2

Error: 2 components

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Last update: May 4, 2022