Problem A: Photo-radar placement
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There are too many bad drivers in a certain European city. In 
particular, there has been a lot of accidents on the bridges over
canals that criss-cross through the city. The city council wants 
to catch bad drivers. Their method of choice is installing photo-radar 
on certain bridges and using them to catch offenders. However,
the cost of buying and maintaining the hardware and processing 
the data are significant. So the council turns to its resident 
Computer Scientist to design an algorithm that would get the 
maximum bang for the buck.

The solution proposed by the Computer Scientist is the following.
He partitions the city into a set of areas A,B,C,......, and decides
to only consider one bridge per area. He also decides to focus on
roads that connect these bridges. Then, a bridge x gets a 
photo-radar if and only if there are two distict city areas A,B 
such that all paths between A and B pass through the bridge x. 

For instance, suppose that we have six areas (A,B,C,D,E,F) with 
seven roads B-C, A-B, C-A, D-C, D-E, E-F and F-C (assume all roads
are two-way). In this configuration, C is the only bridge with a 
photo-radar.

Input
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The input will consist of a city map. The first line contains an
integer n, 1000 >= n > 1, which denotes the number of areas in the 
city. The nodes are numbered 1 thorugh n. The next line contains
an integer r, r>0, which denotes the total number of roads in the
city. The next r lines contain a pair of city areas each; these are
the two areas that a road connects. Assume that the degree of ewch node
is at most 50.

Assume that it is possible to go from each area to another, and that 
the area names given are valid.

Output
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Print the following line (c is the number of photo-radar locations):

c location(s) found at:
followed by c lines, each containing the location name (i.e., area name)
for a photo-radar. The list of areas should be in increasing order.


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


Sample Output
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1 location(s) found at:
1