What are the methods for removing elements from a vector?

There are several different methods for removing elements from a vector.

1. By using the erase() function, elements can be deleted by specifying the iterator position of the element to be removed. For example, vector.erase(vector.begin()) can delete the first element, and vector.erase(vector.begin()+2) can delete the third element.
2. The pop_back() function can be used to remove the last element of a container. For example, vector.pop_back() can remove the last element.
3. By using the clear() function, you can remove all elements from the container. For example, vector.clear() will delete all elements.
4. By using the remove() function, you can delete specific elements from a container. For example, vector.remove(3) can delete all elements with a value of 3.

It is important to note that when using the erase() function to delete elements, the container needs to resize and reallocate memory, thus making it less efficient. On the other hand, deleting elements using pop_back() function only requires reducing the container’s size by 1, making it more efficient.