Breadth-First Search
--------------------

In this problem, you will have to do a breadth-first search of a
directed graph.

Input
-----

The input will consist of multiple instances.  The first line of each
instance will contain two integers n and m, representing the number of
nodes and edges in the graph, respectively.  These values will satisfy
1 <= n <= 100000 and 0 <= m <= 100000.  Following this, there will be
m lines, each containing two integers i and j, where 1 <= i <= n and 
1 <= j <= n, indicating that there is an edge from node i to node j.  
The end of the input will be indicated by a line with m=n=0.

Output
------

For each input graph, output the distance number of edges in the shortest
path from node 1 to each of the other nodes, in the format shown below.
If there is no path from node 1 to some other node, output "no path"
for that node.

Sample Input
------------
5 10
1 2
1 4
2 4
2 5
4 3
4 5
3 5
4 2
5 1
3 4
3 2
1 2
2 1
0 0

Sample Output
-------------
Graph #1
1: 0
2: 1
3: 2
4: 1
5: 2
Graph #2
1: 0
2: 1
3: no path