Question

I have my loop going through vector’s elements. While in this loop some of the elements are being (I want them to be) removed. Although std::vector does not allow to do this, and I would like an alternative.

for(unsigned int j = 0; j < rectArray.size(); j++)
{
 if( rectArray[j] == 2 ) 
  {
   rectArray.erase(rectArray.begin() + j);
  }
//...
}

Do you think a std::list would be good here ? Can I use something else ?

Answer 1

I would suggest modifying your code such that it uses iterators instead of the actual vector. It’s much cleaner and more efficient like this:

for (auto it = rectArray.begin(); it != rectArray.end(); ++it)
{
    // Access the current element with *it
    // If you want you can pass `it` and `rectArray.end()` as
    // the lower and upper bounds of the new collection,
    // rather than doing expensive resizes of the vector.
}

Note that auto is a C++11 feature (the way I used it). If your compiler supports that you might also want to use C++11’s foreach:

for (auto it : rectArray) {
   // same as before
}