span_forest.c : Computes estimates for the number of forests of a graph, input as a 0-1 incidence matrix. Notes: Compile in C++, "g++ -o span_forest span_forest.c". The program does not demand that the matrix is symmetric with 0 diagonal, but uses only the upper triangular part.

permanent.c : Computes the permanent of a nonnegative integer matrix. Notes: Compile in C++, "g++ -o permanent permanent.c".

hafnian.c : Computes the hafnian of a nonnegative integer matrix. Notes: Copy hafnian.c to main.c, in the same directory as Rothberg's code (see above). You can download the .tar directory with the code weighted-match.tar here. Then "make" the codes (this codes are in C, not C++). The program is then run by the command "wmatch".