Codeforces Round 167 (Div. 2)
E
Dima and Horses
Codeforces
2200
原题
← D→
翻译中…

Dima came to the horse land. There are $*n*$ horses living in the land. Each horse in the horse land has several enemies (enmity is a symmetric relationship). The horse land isn't very hostile, so the number of enemies of each horse is at most 3.

翻译中…

Right now the horse land is going through an election campaign. So the horses trusted Dima to split them into two parts. At that the horses want the following condition to hold: a horse shouldn't have more than one enemy in its party.

翻译中…

Help Dima split the horses into parties. Note that one of the parties can turn out to be empty.

翻译中…

Input

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The first line contains two integers $*n*, *m*$ image — the number of horses in the horse land and the number of enemy pairs.

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Next $*m*$ lines define the enemy pairs. The $*i*$-th line contains integers $*a*_{*i*}, *b*_{*i*}$ $(1 ≤ *a*_{*i*}, *b*_{*i*} ≤ *n*; *a*_{*i*} ≠ *b*_{*i*})$, which mean that horse $*a*_{*i*}$ is the enemy of horse $*b*_{*i*}$.

翻译中…

Consider the horses indexed in some way from 1 to $*n*$. It is guaranteed that each horse has at most three enemies. No pair of enemies occurs more than once in the input.

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Output

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Print a line, consisting of $*n*$ characters: the $*i*$-th character of the line must equal "0", if the horse number $*i*$ needs to go to the first party, otherwise this character should equal "1".

翻译中…

If there isn't a way to divide the horses as required, print -1.

翻译中…

样例

Input #1
3 3
1 2
3 2
3 1
Output #1
100
InputCopy OutputCopy
Input #2
2 1
2 1
Output #2
00
InputCopy OutputCopy
Input #3
10 6
1 2
1 3
1 4
2 3
2 4
3 4
Output #3
0110000000
InputCopy OutputCopy
题目信息
题号
272E
时间限制
2 s
内存限制
256 MB
标签
组合数学
构造
图论

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。