message: Avoid consecutive push_back
diff: @@ -117,8 +117,8 @@ persistent_cohomology::Persistent_cohomology<FilteredComplex, persistent_cohomol
  } else {
  while(diags.size() < dim+1) diags.emplace_back();
  auto w = stptr_->vertex_with_same_filtration(t);
  - diags[dim].push_back(v);
  - diags[dim].push_back(w);
  + auto& d = diags[dim];
  + d.insert(d.end(), { v, w });
  }
  }
  return out;
  @@ -152,8 +152,8 @@ persistent_cohomology::Persistent_cohomology<FilteredComplex, persistent_cohomol
  auto v2 = *++i;
  GUDHI_CHECK(++i==std::end(e_vertices), "must be an edge");
  while(diagsinf.size() < dim+1) diagsinf.emplace_back();
  - diagsinf[dim].push_back(v1);
  - diagsinf[dim].push_back(v2);
  + auto& d = diagsinf[dim];
  + d.insert(d.end(), { v1, v2 });
  }
  } else {
  auto et = stptr_->edge_with_same_filtration(t);
  @@ -165,9 +165,8 @@ persistent_cohomology::Persistent_cohomology<FilteredComplex, persistent_cohomol
  if(dim == 0) {
  auto v = *std::begin(stptr_->simplex_vertex_range(s));
  if(diags.size()==0)diags.emplace_back();
  - diags[0].push_back(v);
  - diags[0].push_back(w1);
  - diags[0].push_back(w2);
  + auto& d = diags[0];
  + d.insert(d.end(), { v, w1, w2 });
  } else {
  auto es = stptr_->edge_with_same_filtration(s);
  auto&& es_vertices = stptr_->simplex_vertex_range(es);
  @@ -176,10 +175,8 @@ persistent_cohomology::Persistent_cohomology<FilteredComplex, persistent_cohomol
  auto v2 = *++is;
  GUDHI_CHECK(++is==std::end(es_vertices), "must be an edge");
  while(diags.size() < dim+1) diags.emplace_back();
  - diags[dim].push_back(v1);
  - diags[dim].push_back(v2);
  - diags[dim].push_back(w1);
  - diags[dim].push_back(w2);
  + auto& d = diags[dim];
  + d.insert(d.end(), { v1, v2, w1, w2 });
  }
  }
  }
  