base code : https://github.com/heldstephan/exactcolors

##run approxcolors for an upper bound and a given graph instance.

instance is required in DIMACS-format:

c comments
p edge numberOfVertices numberOfEdges
e node0 node1
.
.
.

1. navigate to bleile folder
2. make approxcolors
3. make testdummy (alternatively 'make testsingle' with specified instance in Makefile)
4. adjust Parameters in approxcolors.cpp


##Using approxcolors through the C API, which is located in c_connector.h

Create a graph with ncount nodes, ecount vertices where edges are stored in an edge list, which
consists of 2*ecount entries and the i-th edge has endpoint elist[2*i] and elist[2*i+1].

int MMTbleile(int ncount, int ecount, int *elist, int *ncolors,
                   COLORset **colorclasses, int L, int T, int time_limit, int lb);

1. ncolors and colorclasses return a best found coloring
2. L specifies the initial iteration limit for tabu search
3. T specifies length of tabu list
4. time_limit is self explanatory
5. lb offers the possibility to give a lower bound to the algorithm
	to proof optimality of a found upper bound and stop before timing out