Question

In my C++ code, I access a map through iterator. Update the map if necessary and re-assign it to class variable. In proceeding statements, I want to use updated map value again. Should I load the map again, refresh the iterator? etc. e.g. the map is:

MapType tbl = device->trust();
MapType::iterator iter_trust = tbl.begin();
tbl.insert(std::pair<int, double> (node->getId().id(), 0.1));

to execute the following on updated value, what should I do?

iter_trust = tbl.find(node->getId().id());

Answer 1

MapType tbl = device->trust();
MapType::iterator iter_trust = tbl.find(node->getId().id());

if (iter_trust == tbl.end()) {
   tbl.insert(std::make_pair(node->getId().id(), 0.1));
   iter_trust = tbl.find(node->getId().id());
}
else {
   tbl[node->getId().id()] = 0.1;
}

So you’ll be sure you upgrade.