I am using boost graph library in my research project about graph theory. One object is testing whether graph G1 has a subgraph isomorphic to another graph G2. I only care about the result, "yes" or "no", and don't expected to find out a isomorphism pattern.

I use the library function vf2_subgraph_iso(), but the third parameter is a callback function which will print out the isomorphic pattern all the time. Is there any way to omit this parameter or eliminate the output pattern. Here is my code snippet:

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vf2_print_callback<Graph, Graph> callback(C4, g);
if (!vf2_subgraph_iso(C4, g, callback) {

        // something;
}
else {
        // something;
}
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