WEBVTT 00:00:00.940 --> 00:00:05.380 It's time for the summary of the final module in the course. We first 00:00:05.380 --> 00:00:09.310 talked about standard array class and how it can be used instead of a 00:00:09.310 --> 00:00:13.660 legacy raw array. Standard array is a templated class. 00:00:13.670 --> 00:00:17.160 The template arguments contain the data type of the elements 00:00:17.160 --> 00:00:19.550 and the number of elements in the array. 00:00:19.840 --> 00:00:21.810 Since the size is a template argument, 00:00:21.810 --> 00:00:24.780 we don't need to allocate a special place in memory to store 00:00:24.780 --> 00:00:28.710 it, so the total memory allocated for the standard array is 00:00:28.710 --> 00:00:31.560 just the total size of all elements. 00:00:32.340 --> 00:00:35.730 Standard array also has an at function which works 00:00:35.730 --> 00:00:37.990 just like a square brackets operator, 00:00:38.000 --> 00:00:42.520 but it also does bound checking. If you want to convert a 00:00:42.520 --> 00:00:46.960 raw array to the standard array, C++20 offers you a new 00:00:46.960 --> 00:00:48.860 to_array function to do that. 00:00:49.940 --> 00:00:52.270 We can create a templated function to pass the 00:00:52.270 --> 00:00:54.920 standard array object as an argument. 00:00:54.930 --> 00:00:57.510 That way, the function will be able to receive an 00:00:57.510 --> 00:01:00.460 array of any data type and size. 00:01:01.240 --> 00:01:05.690 Standard array also offers us some perks like making a copy of all 00:01:05.690 --> 00:01:10.730 elements by simply using the copy assignment operator. Iterators 00:01:10.730 --> 00:01:14.640 serve as an interface between a container object and a function 00:01:14.640 --> 00:01:16.620 from the algorithm library. 00:01:16.630 --> 00:01:22.250 We can pass the standard array's iterators to a function like sort to sort 00:01:22.260 --> 00:01:27.060 all of the elements by value, and we can also use range‑based for loops, 00:01:27.060 --> 00:01:30.260 because they utilize iterators in the background. 00:01:31.140 --> 00:01:33.940 C++20 also provides ranges. 00:01:33.950 --> 00:01:40.290 Ranges are an abstraction on top of iterators. Constrained algorithms from 00:01:40.290 --> 00:01:44.760 the range's namespace can be simpler to use, because all we need to do is to 00:01:44.760 --> 00:01:51.100 pass the container itself, we don't need to use iterators explicitly. Ranges 00:01:51.100 --> 00:01:55.350 library also offers us the ability to create a chain of views to work with 00:01:55.350 --> 00:02:00.520 temporary ranges and form a new perspective on the existing sequential data 00:02:00.520 --> 00:02:01.360 structures. 00:02:02.340 --> 00:02:04.370 If you need dynamic arrays on the heap, 00:02:04.380 --> 00:02:08.550 you can use the vector class from the standard library. Vectors can 00:02:08.550 --> 00:02:11.680 also be resized, so if you want to add more elements, 00:02:11.680 --> 00:02:15.370 vectors will allocate a larger internal array on the heap, 00:02:15.380 --> 00:02:18.710 and move all of the elements from the old array to keep 00:02:18.710 --> 00:02:20.850 them all in one block of memory. 00:02:21.740 --> 00:02:25.050 If you don't know the exact size of the vector at declaration, 00:02:25.060 --> 00:02:27.770 you can use the push_back function to push another 00:02:27.770 --> 00:02:30.650 element to the end of the internal array. 00:02:30.680 --> 00:02:33.260 This will resize the vector automatically, 00:02:33.640 --> 00:02:38.750 but resizing is computationally expensive, so to keep it to minimum, 00:02:38.750 --> 00:02:42.060 we can reserve capacity with the reserve function. 00:02:42.740 --> 00:02:47.120 We can also insert or erase elements at a specific position in the 00:02:47.120 --> 00:02:51.160 vector by using the insert or erase functions. 00:02:52.040 --> 00:02:54.730 If you need to remove a specific value from the vector, 00:02:54.730 --> 00:02:58.520 you can move all of the elements with that value to the end of the vector 00:02:58.520 --> 00:03:03.990 by using the remove function. Then, you can simply delete those elements 00:03:03.990 --> 00:03:08.440 with erase, but there is also a standard erase function which combines 00:03:08.440 --> 00:03:11.860 remove and erase in one single function. 00:03:12.740 --> 00:03:16.380 The main idea around the smart pointer is that it has an 00:03:16.390 --> 00:03:18.850 ownership of the pointed resource. 00:03:18.860 --> 00:03:23.990 That means that a smart pointer is an RAII class, which wraps around the 00:03:23.990 --> 00:03:27.900 raw pointer, so when an object of this class is deleted, 00:03:27.910 --> 00:03:31.550 destructor will also deallocate the owned resource. 00:03:32.340 --> 00:03:36.600 Standard library offers us an exclusive ownership of the resource 00:03:36.600 --> 00:03:41.670 with unique pointers. Unique pointers cannot be cloned, they can only 00:03:41.670 --> 00:03:44.460 transfer ownership with move semantics. 00:03:45.340 --> 00:03:48.280 Shared pointers don't have exclusive ownership, 00:03:48.290 --> 00:03:52.150 they co‑own resources with other shared pointers. 00:03:52.540 --> 00:03:55.920 The amount of shared pointers which point to the same resource is kept 00:03:55.920 --> 00:03:58.960 inside of a dynamically allocated control block. 00:03:59.340 --> 00:04:02.040 Once the last one of these pointers is deleted, 00:04:02.050 --> 00:04:07.090 destructor will deallocate the owned resource. Weak pointers 00:04:07.090 --> 00:04:10.540 have temporary ownership, they can only point to the resources 00:04:10.550 --> 00:04:12.900 owned by other shared pointers. 00:04:13.120 --> 00:04:16.760 When we want to use them to access the pointed resource, we have to use the 00:04:16.760 --> 00:04:20.160 lock function to turn them into a shared pointer first. 00:04:21.040 --> 00:04:24.730 And, that's it, we are finally at the end of the whole course. 00:04:24.740 --> 00:04:28.070 I hope that you gained a lot of new insight about the world of 00:04:28.070 --> 00:04:30.430 pointers and memory management. 00:04:30.440 --> 00:04:34.250 Don't hesitate to join the discussion if you have any questions. 00:04:34.260 --> 00:04:38.050 Thank you for watching, and good luck on your future endeavors.