@gentoobro it's an integer vector, so the comparison works as expected. I don't know if the edit federated, the gist of it is that I did a backwards scan and broke the loop on the first match, which was always on the first iteration because of the j = i; as a result, there was no vertex deduplication. I think I was trying to fix a bug with repeating vertices, and for some reason I didn't add a separate counter and tried to do it with just two variables.