If outfile has a suffix, i.e., has the form base.sfx, then the files will have the same name as above, except appended with .sfx.
The block-cutvertex tree of ith graph is written to outfile_n_T, with an appended suffix if specified.
By default, each input graph is printed, with each block given as a subgraph whose name is a concatenation of the name of the input graph, the string "_bcc_" and the number of the block.