http://noi.openjudge.cn/ch0306/2392/
描述
The steamy, sweltering summers of Wisconsin's dairy district stimulate the cows to slake their thirst. Farmer John pipes clear cold water into a set of N (3 <= N <= 99999; N odd) branching pipes conveniently numbered 1..N from a pump located at the barn. As the water flows through the pipes, the summer heat warms it. Bessie wants to find the coldest water so she can enjoy the weather more than any other cow.
She has mapped the entire set of branching pipes and noted that they form a tree with its root at the farm and furthermore that every branch point has exactly two pipes exiting from it. Surprisingly, every pipe is exactly one unit in length; of course, all N pipes connect up in one way or another to the pipe-tree.
Given the map of all the pipe connctions, make a list of the distance from the barn for every branching point and endpoint.Bessie will use the list to find the very coldest water.
The endpoint of a pipe, which might enter a branching point or might be a spigot, is named by the pipe's number. The map contains C (1 <= C <= N) connections, each of which specifies three integers: the endpoint E_i (1 <= E_i <= N) of a pipe and two branching pipes B1_i and B2_i (2 <= B1_i <= N; 2 <= B2_i <= N). Pipe number 1 connects to the barn; the distance from its endpoint to the barn is 1.
输入
* Line 1: Two space-separated integers: N and C
* Lines 2..C+1: Line i+1 describes branching point i with three space-separated integers: E_i, B1_i, and B2_i
输出
* Lines 1..N: Line i of the output contains a single integer that is the distance from the barn to the endpoint of pipe i
样例输入
5 2 3 5 4 1 2 3
样例输出
1 2 2 3 3
提示
INPUT DETAILS:
The input above describes this pipe map:
+------+
| Barn |
+------+
| 1
*
2 / \ 3
*
4 / \ 5
OUTPUT DETAILS:
Pipe 1 is always distance 1 from the barn. Pipes 2 and 3 connect directly to pipe 1 and thus are distance 2 from the barn. Pipes 4 and 5, which connect to pipe 3, are distance 3 from the barn.
翻译：
描述
威斯康辛州奶牛场闷热的夏天刺激着奶牛去解渴。农夫约翰将清澈的冷水注入一组N (3 <= N <= 99999;N奇数)分支管道方便编号为1..从谷仓的泵里取氮。当水流过管道时，夏天的热量使它变暖。贝茜想找到最冷的水，这样她就可以比其他奶牛更享受天气了。
她绘制了整个分支管道的地图，并注意到它们形成了一棵树，根在农场，而且每个分支点都有两个管道出口。令人惊讶的是，每根管子的长度恰好是一个单位;当然，所有的N个管道都以这样或那样的方式连接到管道树。
给定所有管道连接的映射，列出每个分支点和端点到仓库的距离。贝西会用这个列表找到最冷的水。
管道的端点(它可能进入一个分支点，也可能是一个插口)由管道的编号命名。映射包含C (1 <= C <= N)个连接，每个连接指定三个整数:一个管道的端点E_i (1 <= E_i <= N)和两个分支管道B1_i和B2_i (2 <= B1_i <= N;2 <= B2_i <= N)。1号管道连接到谷仓;从它的端点到谷仓的距离是1。
输入
*第一行:两个用空格分隔的整数:N和C
*第2行..C+1:第i+1行描述了分支点i和三个用空格分隔的整数:E_i, B1_i和B2_i
输出
*线1 . .N:输出的第i行包含一个整数，从仓库到管道i端点的距离
样例输入
5个2
3 5 4
1 2 3
样例输出
1
2
2
3.
3.
提示
输入详细信息:
上面的输入描述了这个管道映射:
+------+
| Barn |
+------+
| 1
*
2 / \ 3
*
4 / \ 5
输出详细信息:
1号管道离谷仓总是有一段距离。管道2和3直接连接到管道1，因此距离谷仓2。4号和5号管道连接到3号管道，距离谷仓的距离为3。