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p035: [Week 12] Bicoloring
Keyword: Miguel Revilla 2000-08-21

Difficulity: 2 | Test Data Sets: 5 (Hidden) | Judging: Traditional Judge
Accepted : 251 Times | Submit :941 Times | Clicks : 2819
Accepted : 149 Users | Submit : 163 Users | Accepted rate : 91%
Time Limit :1000 ms | Memory Limit : 64000 KBytes
Update : 2015-06-12 09:27


In 1976 the "Four Color Map Theorem" was proven with the assistance of a computer. This theorem states that every map can be colored using only four colors, in such a way that no region is colored using the same color as a neighbor region.

Here you are asked to solve a simpler similar problem. You have to decide whether a given arbitrary connected graph can be bicolored. That is, if one can assign colors (from a palette of two) to the nodes in such a way that no two adjacent nodes have the same color. To simplify the problem you can assume:



The input consists of several test cases. Each test case starts with a line containing the number n ( 1 < n < 200) of different nodes. The second line contains the number of edges l. After this, l lines will follow, each containing two numbers that specify an edge between the two nodes that they represent. A node in the graph will be labeled using a number a (0 <= a < n).

An input with n = 0 will mark the end of the input and is not to be processed.


You have to decide whether the input graph can be bicolored or not, and print it as shown below.

Sample Input:help

若題目沒有特別說明,則應該以多測資的方式讀取,若不知如何讀取請參考 a001 的範例程式。
0 1
0 2
0 3
0 4
0 5
0 6
0 7
0 8
0 1
1 2
2 0

Sample Output :


Hint :

Author :

Miguel Revilla 2000-08-21 (Manager: taskmanager)

  Solve it!   Status Forum

20184. EEL
(0ms, 114KB, 397B)
5095. rainism
(0ms, 638KB, 377B)

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