Copy std::map into std::vector of pairs

Question

I\'m trying to copy a map into a vector of pair, so I can then sort the vector by the second data member of the pairs. I have resolved this doing like this:

Answer 1

Just use std::vector's assign member function.

//no need to call reserve, bidirectional iterators or better will compute the size and reserve internally.
vectorWordsList.assign(mappedWordsList.begin(), mappedWordsList.end());

If you have existing values in the vector that you don't want overwritten then use insert instead like

vectorWordsList.reserve(vectorWordsList.size() + mappedWordsList.size()); // make sure we only have a single memory allocation
vectorWordsList.insert(vectorWordsList.end(), mappedWordsList.begin(), mappedWordsList.end());