You can just reduce the size value and manually call the destructor on all the objects that don't exist anymore. For loops like this use the standard algorithms: Personally I don't see the point. I can achieve the same effect in one line:. That's an okay guide for reference, but I'd highly recommend searching for pages that give in-depth information about std::vector s.
There's a lot going on under the hood, and one general guide cannot teach you everything. I'm not sure how far you want to go with the STL minus std::vector of course , but I'd still make use of it. Without it, your code will be too C-like and improper use of raw pointers also C-like could attract all sorts of bugs. I'd really test the shifting in both erase es. It's not quite a straightforward algorithm. For one thing, your algorithm will eventually leave a garbage value at the very end if shifting left.
Correcting that won't be so easy, which is why this may need to be approached differently. What happens if you increment the size again?
Yes, that element will still be there. Vectors are always shrinking and growing, so do just that. Despite the performance hit that you're trying to avoid, this method is not at all like the original.
It is supposed to call the destructor for the removed element to make sure it's destroyed for good. Why are you forcing the size to 0 in clear? Your destruction method should reduce the size itself, thereby giving you an accurate count of the remaining elements which should be 0.
Again, don't take the easy way out in favor of performance. Do what the original is supposed to do. Here's a rough idea of how your declarations and definitions should be structured. These can be in separate files. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. Template vector class Ask Question. Asked 8 years, 5 months ago. Active 8 years ago.
A reference to the element subscripted in the argument. If position is greater than the size of the vector, at throws an exception.
If the return value of at is assigned to a reference , the vector object can be modified. If the return value of back is assigned to a reference , the vector object can be modified.
For more information, see Checked iterators. A random-access iterator addressing the first element in the vector or to the location succeeding an empty vector. Always compare the value returned with vector::end to ensure it's valid. If the return value of begin is assigned to an vector::iterator , the vector object can be modified. The member function resize will be more efficient if sufficient memory is allocated to accommodate it. Use the member function reserve to specify the amount of memory allocated.
Returns a const iterator that addresses the first element in the range. Typically, it's used in with the auto type deduction keyword, as shown in the following example. In the example, consider Container to be a modifiable non- const container of any kind that supports begin and cbegin. Returns a const past-the-end iterator that points to the element following the last element of the vector.
A const past-the-end iterator for the vector. It points to the element following the last element of the vector. That element is a placeholder and shouldn't be dereferenced. Only use it for comparisons.
Typically, it's used with the auto type deduction keyword, as shown in the following example. In the example, consider Container to be a modifiable non- const container of any kind that supports end and cend. A type that provides a random-access iterator that can read a const element in a vector. An iterator is more commonly used to access a vector element. A type that provides a reference to a const element stored in a vector. It's used for reading and doing const operations.
A type that provides a random-access iterator that can read any const element in the vector. See rbegin for an example of how to declare and use an iterator. A const reverse random-access iterator addressing the first element in a reversed vector or addressing what had been the last element in the unreversed vector. Returns a const past-the-end reverse iterator that points to the element following the last element of the reversed vector.
A const reverse past-the-end iterator for the reversed vector. It points to the element following the last element of the reversed vector, which is the same as the element before the first element of the non-reversed vector. With the return value of crend suitably decremented , the vector object can't be modified. In most cases it should be used instead of directly dealing with buffer objects. The internal storage is allocated in a specific OpenCL context which is passed as an argument to the constructor when the vector is created.
For example, to create a vector on the device containing space for ten int values:. The Boost. It can be used with any of the STL-like algorithms provided by Boost. Compute including copy , transform , and sort among many others.
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