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#1714. [Usaco2007 China]Treasure 财富

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Description

 

Input

    1行输入N,之后N行每行输入一对整数,描述一条道路.

Output

 输出宝藏的埋藏方式种数.

Sample Input

4
1 2
2 3
3 1
1 4

INPUT DETAILS:

Here is a drawing of the roads and the intersections.

4---1---2
\ /
3

Sample Output

3

OUTPUT DETAILS:

The treasure can be buried at any intersection. However, burying it at
intersections 2 and 3 yields maps that are identical to each other. So the
total number of distinct treasure maps is 3.

Hint

Source

Gold