Check out example codes for "when a vector in c++ is resized what happens to the elements of the vector". It will help you in understanding the concepts better.
Code Example 1
The C++ function std::vector::resize() changes the size of vector. If n is smaller than current size then extra elements are destroyed. If n is greater than current container size then new elements are inserted at the end of vector. If val is specified then new elements are initialed with val.
Learn ReactJs, React Native from akashmittal.com