[Solved] Vectors And Merging

I think your problem is that these lines:

if (que1.empty()){
    for (int m = j; m < counterq2; m++){
        que_merge.push_back(que2.at(m));
    }
} else {
    for (int l = i; l < counterq1; ++l) {
        que_merge.push_back(que1.at(l));
    }
}

doesn’t do what you expect.

As far as I can see, your idea is to merge the remaining element from either que1 or que2.

However, that is not what you get from this code as the elements in que1 and que2 is never erased. In other words – the check for an empty queue is rather meaningless and you can’t be sure that all elements are added to que_merge

So when you do:

for (int l = 0; l < (counterq1+counterq2); l++) {
    cout << que_merge.at(l) << endl;
}

you may read beyond the number of elements in que_merge

Tip:

Don’t count the number of elements your self. Use size() (like que_merge.size()) instead. For instance:

for (int l = 0; l < que_merge.size(); l++) {
    cout << que_merge.at(l) << endl;
}

or a range based loop like:

for (const auto& s : que_merge) {
    cout << s << endl;
}