new & delete Operators For Dynamic Memory Allocation

new & delete Operators For Dynamic Memory Allocation | C++ Tutorial

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2 жыл бұрын

How to use the new and delete operators in C++ to dynamically allocate memory. Source code: github.com/portfoliocourses/c.... Check out www.portfoliocourses.com to build a portfolio that will impress employers!

Пікірлер: 52

@mrtom-a-hawk6732 8 ай бұрын

The clarity of this video is beyond incredible. Fantastic work!

@PortfolioCourses 8 ай бұрын

I'm glad you enjoyed it! :-)

@chickenmadness1732 Жыл бұрын

I love the commented diagram you made below the code. Really helped a bunch of stuff click.

@PortfolioCourses Жыл бұрын

I'm glad you enjoyed it! 🙂

@dishmaster4140 9 ай бұрын

From the bottom of my heart, thank you SO MUCH for this. I have been having the hardest time understanding pointers because no resource I had found was hitting quite the right spot on why we should care about pointers, but you did it. Thank you for taking the time to demonstrate the memory allocation and your attention to discussing that side of things. I have been pulling my hair out over this, and I cannot tell you how overjoyed I am to have found this video.

@kazikmajster5650 3 ай бұрын

My God, if I had just watched this 15 minute video before starting my project it would eliminate like 2 hours of confusion...

@sournois90 Жыл бұрын

are you an angel? ive been trying to understand this for days and you're the only one that made it make sense

@PortfolioCourses Жыл бұрын

I'm so glad to hear this video was able to help you out! :-)

@mihaibozian Жыл бұрын

best explanation about dynamic mem allocation

@PortfolioCourses Жыл бұрын

Thank you for the positive feedback Bozian, I’m glad you enjoyed it! :-)

@lexdose4104 5 ай бұрын

Ive been learning C++ as a 1st year CS student from around 5 months now and Im currently dealing with pointers from my book resources. I was very confused about the concept of new and delete operators and was wondering why I should use them and now Im starting to understand their functions and how important they are on memory management, thank you so much!

@PortfolioCourses 5 ай бұрын

You’re very welcome I’m glad the video was helpful for you to learn these ideas! :-)

@muhammadluqman3452 Жыл бұрын

great playlist , you are a hidden gem!

@PortfolioCourses Жыл бұрын

Thank you Muhammad! 😀

@SAURABHJAIN1989 3 ай бұрын

7:14 int *ptr_to_int = new int(5); // to store an integar. double *array = new double[5]; //to store an array. So, round brackets ( ) to allocate single value and square brackets [ ] to allocate an array with the new operator. So, the basic syntax for the new operator is: datatype *var_name = new datatype(); or datatype *var_name = new datatype(val); //when we pass a value (might be an int or string or any other data type)

@uclocnguyenvo422 Жыл бұрын

oh shit this tutorial is so good -_- u deserve millions of subscribers

@PortfolioCourses Жыл бұрын

Thank you for the positive feedback Đức! :-)

@Ivy891 4 ай бұрын

amazing video !

@PortfolioCourses 4 ай бұрын

I'm glad you enjoyed it! :-)

@mouli4867 6 ай бұрын

Thank for this tutorial. But I couldn’t find out a tutorial of yours on placement new. Please can we have a tutorial on that whenever you have time. Thank you once again.

@YeabsiraAlemu-bx9si 7 ай бұрын

Fantastic

@stonedcodingtom9097 Жыл бұрын

Thanks!

@PortfolioCourses Жыл бұрын

You’re very welcome! :-)

@i-yusuf 2 жыл бұрын

Hey man, thanks for making c++ playlist, Which IDE are you using ?

@PortfolioCourses 2 жыл бұрын

You’re welcome Yusuf! I am using Xcode on a Mac in most videos, though sometimes I use Visual Studio Code and the terminal/compiler instead.

@user-jz5pu3lx8w 3 ай бұрын

Just out of curiosity, what is the font used for coding in this video? It looks quite pleasant to me.

@mirellesv Жыл бұрын

great video! at 6:47, you have declared a pointer that stores the adress of the first element of an array, right? so, when assigning the values to the array, why couldn't we say, for example, *array[0] = 5?

@PortfolioCourses Жыл бұрын

Great question! 🙂You can use pointer notation with arrays but it looks a bit different than that, this video gets into that topic: kzfaq.info/get/bejne/nr13jKV-tJuZY3U.html.

@mirellesv Жыл бұрын

@@PortfolioCourses this has been bugging me for a while 😅, I'll definitely watch it! thank you!

@PortfolioCourses Жыл бұрын

You're welcome! :-D

@tanang2565 Жыл бұрын

truly appreciate your video ! Btw, can you link the document related to constructor syntax (name(name) {}) in 11:34 please ? I havent seen it before. Thank you.

@PortfolioCourses Жыл бұрын

That's called a member initializer list, this video covers the concept: kzfaq.info/get/bejne/jpeUeriEu9TFpoU.html. There is some more 'official documentation' here: en.cppreference.com/w/cpp/language/constructor. 🙂

@msk1754 4 күн бұрын

Thanks for making video! If base adress is 0x0001, ptr_to_ have to be allocated 0x0001+ sizeof(int)?

@CPPLover-df9zw Жыл бұрын

Would it not be better to declare the big_array pointer out of the try-block and initialize it with a nullptr? After the allocation happens and the main terminates, this is going to result in a memory leak.

@PortfolioCourses Жыл бұрын

That example was to demonstrate memory allocation failure, so no memory was going to be allocated. If no memory is allocated, we don't need to delete/free the allocated memory. Also, when the main function terminates all memory is going to be "released". When the program stops executing there are no more memory leaks.

@masihaahmadi7663 8 ай бұрын

great

@PortfolioCourses 8 ай бұрын

I’m glad you enjoyed it! :-)

@mba2ceo 7 ай бұрын

placement NEW link ?

@mba2ceo Жыл бұрын

can I use a *PTR to delete an OBJECT ?

@PortfolioCourses Жыл бұрын

Yes if PTR is set to point to an object instance then you can use "delete PTR" to delete the object. :-)

@Victor-fl8ex 2 жыл бұрын

didnt you cover this topic in previous videos?

@PortfolioCourses 2 жыл бұрын

Nope, I’ve used them in previous videos but haven’t been able to cover them yet. I’ve been hoping to cover them for awhile now.

@Victor-fl8ex 2 жыл бұрын

@@PortfolioCourses I see. Btw, could you cover Maps in the short term? Idk if they are on your planed videos (I guess), but it would be a very interesting topic along with unique_ptrs and stuff. Good Video again Kevin!. Keep up with the good content!

@PortfolioCourses 2 жыл бұрын

I’m not sure when I’ll cover Maps but hopefully one day I’ll get to it all. :-)

@korngsamnang 2 жыл бұрын

int x = 5; int *y = &x; //s1 int *y = new int(x); //s2 Sir, what is difference between s1 and s2 ?

@PortfolioCourses 2 жыл бұрын

s1 will have y be a pointer to variable x. In other words, y will store the memory address that the variable x is located at. x is located in a place in memory called the stack. s2 uses dynamic memory allocation with the new operator. The new operator will create space to store a new int value, in a place in memory called the heap. That new int value will be set to whatever value x is set to, in this case 5. This new int value will have no relationship to x though. The value of x is used to set this new int value, that's all. And y will store the memory address of this new int value on the heap.

@korngsamnang 2 жыл бұрын

@@PortfolioCourses Thank you sir for clarification.

@PortfolioCourses 2 жыл бұрын

@@korngsamnang You're welcome! 😀

@ivans7 Жыл бұрын

What is the editor name?

@PortfolioCourses Жыл бұрын

In this video I am using Xcode on a Mac. :-)

@imveryhungry112 6 ай бұрын

im too dum to understand any of this

@Daniel-vs7it 6 ай бұрын

(If im not wrong) we need to make this a pointer to point to the address of the int, it's like if we were making int* ptr = &var but instead of using a already initialized variable we create one with the new keyword, the pointer just points to the address of the new dynamically allocated variable, after we finish we need to use delete because if we dont do it we'll cause a memory leak.