CR07C3P5 - BICIKLI

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A bicycle race is being organized in a land far, far away. There are N town in the land, numbered 1
through N. There are also M one-way roads between the towns. The race will start in town 1 and end
in town 2.
How many different ways can the route be set? Two routes are considered different if they do not use
the exact same roads. 

A bicycle race is being organized in a land far, far away. There are N town in the land, numbered 1 through N. There are also M one-way roads between the towns. The race will start in town 1 and end in town 2. How many different ways can the route be set? Two routes are considered different if they do not use the exact same roads. 

Input

The first line of input contains two integers N and M (1 ≤ N ≤ 10 000, 1 ≤ M ≤ 100 000), the number

of towns and roads.

Each of the next M lines contains two different integers A and B, representing a road between towns A

and B.

Towns may be connected by more than one road. 

Output

Output the number of distinct routes that can be set on a single line. If that number has more than nine

digits, output only the last nine digits of the number. If there are infinitely many routes, output "inf". 

Example

Input:
6 7
1 3
1 4
3 2
4 2
5 6
6 5
3 4 

Output:
3
Input:
6 8
1 3
1 4
3 2
4 2
5 6
6 5
3 4
4 3 

Output:
inf
Input:
31 60
1 3
1 3
3 4
3 4
4 5
4 5
5 6
5 6
6 7
6 7
…
…
…
28 29
28 29
29 30
29 30
30 31
30 31
31 2
31 2 

Output:
073741824 


Added by:Ahmed Salem [mrtempo]
Date:2015-01-17
Time limit:1s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ASM64 JS-MONKEY
Resource:COCI 2006/2007 #3 (http://hsin.hr/coci/archive/2006_2007/contest3_tasks.pdf)