This is the raw data for the graph
matr1 = {{0, 0, 0, 0, 1, 1, 0}, {0, 0, 0, 0, 0, 1, 0}, {0, 0, 0, 0, 0,0, 1},
{0, 0, 0, 0, 0, 0, 0}, {1, 0, 0, 0, 0, 0, 0}, {1, 1, 0, 0, 0, 0, 0}, {0, 0, 1, 0, 0, 0, 0}};
g = AdjacencyGraph[matr1, VertexLabels -> "Name", ImagePadding -> 10]
That's what gives me a built-in function. If you try a littl it's easy to get all the paths which have 4 vertices.
Reap[DepthFirstScan[g, #, {"ForwardEdge" -> Sow, "BackEdge" -> Sow,
"FrontierEdge" -> Sow, "CrossEdge" -> Sow}]][[2]] & /@ Range@Length@matr1 // ColumnForm
Here is the 2nd answer that I got with my own function of in-depth-search (each path passes through 4 vertices, ie it consists of 3 edges):
{
{1, 5, 1, 5},
{1, 5, 1, 6},
{1, 6, 1, 5},
{1, 6, 1, 6},
{1, 6, 2, 6},
{2, 6, 1, 5},
{2, 6, 1, 6},
{2, 6, 2, 6},
{3, 7, 3, 7},
{5, 1, 5, 1},
{5, 1, 6, 1},
{5, 1, 6, 2},
{6, 1, 5, 1},
{6, 1, 6, 1},
{6, 1, 6, 2},
{6, 2, 6, 1},
{6, 2, 6, 2},
{7, 3, 7, 3}
}
Of course, I want DepthFirstScan to gave the same result. And I do not know how to make it.
Any advice?
Thanks,
Gregory
