Bitwise Operators and WHY we use them

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  • Опубликовано: 23 ноя 2024

Комментарии • 134

  • @loayalsaid6343
    @loayalsaid6343 Год назад +55

    small missed detail, : the bitwise, & and | or whatever, they look if both are set, meaning both are one, not just matching, because if both are 0 for example, & will give zero and not 1
    The video is amazing, Thank you, really!.

    • @alexhyettdev
      @alexhyettdev  Год назад +31

      That is a very good point, I should have mentioned that in the video. Thank you for pointing it out.
      For those finding this comment in the future:
      IF:
      a = 1
      b = 1
      THEN:
      a & b = 1
      IF:
      a = 0
      b = 0
      THEN:
      a & b = 0

    • @AntiAtheismIsUnstoppable
      @AntiAtheismIsUnstoppable 9 месяцев назад +1

      I mean... how can anyone call himself a programmer and then not know the most basic of how computers operate, which literally can be learned in one day?
      This is like claiming to be a matematician, but not knowing how addition works.
      I will never ever trust any programmer who doesn't know the most basic of his own tool.

    • @loayalsaid6343
      @loayalsaid6343 9 месяцев назад +4

      I know, and appreciate what you said,
      but you know, mistakes happens, and he said he forgot about it, now he does not know about it.
      buy anyway, Good luck with your learniing process.

    • @witchoutcandy
      @witchoutcandy 8 месяцев назад

      so in the XOR example:
      READ_WRITE = 4
      WRITE_PERMISSION = 2
      EXECUTE_PERMISSION = 1
      userPermissions ^= WRITE_PERMISSION
      this equals 4 because 6^2 is 110^010, that IS 100, right?
      i've thinking... the userPermissions was 7 because of the last operator example, so 111^010 was going to be 5, and the userPermissions "lost" WRITE_PERMISSION but didnt lost execute_permission and read_permission :0 epic

    • @gabeznl3591
      @gabeznl3591 7 месяцев назад

      Also, how can the binary number 0011 equals to 6? It's always 3 in decimal...

  • @johningram2153
    @johningram2153 8 месяцев назад +16

    I've been using the term "bit" when explaining unix permissions ot people for over 25 years, and never understood why. Great video.

  • @TVParsley
    @TVParsley 6 месяцев назад +5

    You explained in 8 minutes what my CS professor couldn’t explain in an hour! Great video!

  • @lanniekin
    @lanniekin 2 года назад +22

    Thank you for this! I've been a game developer for a while and had never had to deal with this concept, but it's been thrown at me with very little explanation in the cybersec course I'm taking. This was very helpful :)

    • @alexhyettdev
      @alexhyettdev  2 года назад

      I am glad you found it helpful. They are definitely one of the lesser used bits of programming.

  • @cannabisanomaly
    @cannabisanomaly 5 месяцев назад +1

    I always come back to this video to refresh my terrible memory on bitwise operations. Thank you Alex!

  • @IsraelSilva-ho8yc
    @IsraelSilva-ho8yc 2 месяца назад +1

    Thank you so much for this man, got a task at work dealing with this and was a "bit" lost 🥁

  • @mr.luxxyandreneo5168
    @mr.luxxyandreneo5168 Год назад +2

    Sir really , the rwx ex. from linux was amazing , none told us such deeply, thanks for relating bin no with programming & with linux, just amazing

    • @alexhyettdev
      @alexhyettdev  Год назад +1

      Thank you for the kind words. I am glad my video was helpful!

  • @brianmwaniqi
    @brianmwaniqi 15 дней назад

    Great explanation as well as examples given for the application of bitwise operations

  • @Nonsense116
    @Nonsense116 3 месяца назад

    excellent video! I'm a Java & React dev. I've been getting into C lately reading the K&R book and was having a hard time internalizing the bitwise operators. This is exactly what I needed.

  • @ShermukhammadKarimov
    @ShermukhammadKarimov 10 месяцев назад

    Thank you so much. You helped me with my university exams. Keep going. Well done.

  • @numbertumbers529
    @numbertumbers529 2 года назад +6

    This was very well-made and informative! You deserve a lot more than 94 subscribers!

    • @alexhyettdev
      @alexhyettdev  2 года назад +1

      Thank you very much, I am glad you liked it.

    • @bouzie8000
      @bouzie8000 8 месяцев назад +3

      oh how much he has grown since this comment

  • @paval1s69
    @paval1s69 2 года назад +4

    Nice! Already learned it but it was still great as a refresher and also a great introduction for newbies to the topic. A shame that the channel is not that big yet

    • @alexhyettdev
      @alexhyettdev  2 года назад

      Thanks! I have only started posting regularly at the start of this month so still early days 🤞🏻

  • @Ctrl_Alt_Elite
    @Ctrl_Alt_Elite Год назад

    I'm learning DSA atm, and came across a constant time solution for the Power of 2 problem that uses the AND bitwise operator
    AMAZING videos, watched both the binary & bitwise operators vids and learned a tonne! Thanks a lot! 😁

    • @alexhyettdev
      @alexhyettdev  Год назад

      Thanks for sharing, I am glad my videos could help!

  • @abeldamtew2004
    @abeldamtew2004 7 месяцев назад +1

    thanks for the awesome explanation and it is good to know when and how to use them.

  • @oglothenerd
    @oglothenerd Год назад +5

    Well, I just learned something cool about UNIX file permissions! I love this, because I use Arch, btw.

    • @alexhyettdev
      @alexhyettdev  Год назад +1

      That's great! I used Arch a lot when I was younger. Back when I had time to customise everything lol

    • @oglothenerd
      @oglothenerd Год назад +1

      @@alexhyettdev Lol.

    • @oglothenerd
      @oglothenerd Год назад +1

      @@alexhyettdev I am 14, so, yeah... XD

    • @alexhyettdev
      @alexhyettdev  Год назад

      @@oglothenerd I remember Arch Linux being really fast. I screwed something up though and couldn’t boot. 🤦🏻‍♂️

  • @Tech-Dev
    @Tech-Dev 11 месяцев назад

    Cheers for making this concept so easy to understand.

  • @AFriendOfYours0
    @AFriendOfYours0 Год назад

    Thank you so much. I was trying to make sense of some code I came across on GitHub and I had no idea what was going on until I watched this. Didn't think I'd have to deal with bitwise operators in JavaScript haha. Loved the simple explanation and the lighting/graphics.

    • @alexhyettdev
      @alexhyettdev  Год назад +1

      They are definitely quite confusing if you haven’t seen them before. Even if you have it can take a little while to work out what is actually doing.

  • @SaMcfc05
    @SaMcfc05 Год назад

    Thank you, this makes things a lot simpler to understand

  • @amaniabid4476
    @amaniabid4476 Год назад

    thank you for this because I get it very easy when you explain it

    • @alexhyettdev
      @alexhyettdev  Год назад

      You’re welcome! I am glad I could help.

  • @mikeh7704
    @mikeh7704 9 месяцев назад +1

    This reminds me of the days I was learning Z80 machine language programming. Nice video! Are there no bitwise rotate operators, or are they rarely needed in higher-level languages?

  • @thoniasenna2330
    @thoniasenna2330 5 месяцев назад

    great, many thanks from Brazil!

  • @timi_t_codes
    @timi_t_codes Год назад

    You keep things so simple!! I would love to teach like you do.

    • @alexhyettdev
      @alexhyettdev  Год назад +1

      Thank you for the kind words! I have never really taught anything before doing this channel. You never know what you can do!

  • @luis.barragan
    @luis.barragan Год назад

    This was a really professional video, straight to the point. Thanks for saving my day.

    • @alexhyettdev
      @alexhyettdev  Год назад

      You are welcome. I am glad you found it useful.

  • @davidvillalobos3854
    @davidvillalobos3854 Год назад

    good video,very simple, straight to the point and the example of user permission was great and easy to follow. Thanks

  • @senriofthealexis3998
    @senriofthealexis3998 8 месяцев назад

    Very concise and informative, thank you Alex

  • @PauloGosen
    @PauloGosen 10 месяцев назад

    Thank you Alex, I really learned something with this video. Keep it up

  • @mossabDiae
    @mossabDiae Год назад +2

    Great video Alex and well explained!
    I've been using Linux in a while and it's the first time to know the origin behind choosing those exact numbers for files permission, learned a lot!
    Thank you, subscribed.

    • @alexhyettdev
      @alexhyettdev  Год назад +1

      Thank you! Yes I don't think many people realise where those numbers come from. It does seem quite arbitrary at first glance.

  • @DaveDemers69
    @DaveDemers69 Год назад +1

    Thank you, this helped a ton!

  • @jewsefjones
    @jewsefjones 5 месяцев назад

    Nice vid I would of liked to see the 0 0 table row and some examples uses for the last few operators

  • @wypimentel
    @wypimentel 9 месяцев назад

    Yeah, this topic was scary to me but you make it seems easy, thanks!

  • @arhanghosh2744
    @arhanghosh2744 8 месяцев назад

    Wonderfully explained. Great video

  • @MohammedRayaanPasha
    @MohammedRayaanPasha 5 месяцев назад

    couldn't get better explanation!

  • @rcnhsuailsnyfiue2
    @rcnhsuailsnyfiue2 Месяц назад

    Great video and excellent explanation 👍

  • @peaceomohimua1183
    @peaceomohimua1183 27 дней назад

    U re a life saver.... God bless u

  • @hernanphillip334
    @hernanphillip334 Год назад

    Very very nice video sir, it has helped me out a lot!

    • @alexhyettdev
      @alexhyettdev  Год назад +1

      That's great! I am glad it helped.

  • @bouzie8000
    @bouzie8000 8 месяцев назад

    Informative and concise video. Good stuff

  • @Xander95X
    @Xander95X Год назад

    Wow, this video is great, super succinct and explained very clearly.

  • @zmo__6992
    @zmo__6992 4 месяца назад

    This a very wonderful video. thanks you!

  • @MrOvergaming
    @MrOvergaming 6 месяцев назад

    I clicked on the like button before strarting the video!

  • @Dallascalo
    @Dallascalo 6 месяцев назад

    Now it makes more sense!

  • @vincentzacks9584
    @vincentzacks9584 8 месяцев назад

    Excellent explanation, thanks mate!

  • @IndisputableConnoisseur
    @IndisputableConnoisseur Год назад +2

    this is gold

    • @alexhyettdev
      @alexhyettdev  Год назад +1

      Thank you for the kind comment. I am glad it was useful.

  • @Honest_Reply900
    @Honest_Reply900 7 месяцев назад

    Very informative video, thanks and making and sharing it

  • @ShiloBuff
    @ShiloBuff 7 месяцев назад

    Great explanation. Thanks

  • @MrKruges
    @MrKruges 8 месяцев назад

    This is so helpful. Thank you!

  • @blaxpow
    @blaxpow Год назад +1

    That's excellent content. Good explanation and video editing. +1 subscriber 🎉

    • @alexhyettdev
      @alexhyettdev  Год назад

      Thanks Wesley! Glad to have you here, welcome 👋

  • @wangxuerui9949
    @wangxuerui9949 8 месяцев назад

    What an awesome video! Super helpful!!

    • @alexhyettdev
      @alexhyettdev  8 месяцев назад

      Thank you, I am glad you liked it.

  • @artemmozharov2492
    @artemmozharov2492 9 месяцев назад

    you can use shifts to multiply by 2pow n and there is also >>> operator or

  • @unidentifiedpy
    @unidentifiedpy 6 месяцев назад

    damn man, you should've been my professor in college. now I'm gonna your student on every vid. cheers!

  • @MoolsDogTwoOfficial
    @MoolsDogTwoOfficial 7 месяцев назад

    This'll be helpful for going into raw mode (UNIX).

  • @Ivanesenses
    @Ivanesenses 4 месяца назад

    thanks Rayan!

  • @moishie20
    @moishie20 8 месяцев назад

    Thanks. Great video

  • @kevinpellerin6715
    @kevinpellerin6715 Год назад

    Programming can be so high level, coming from microprocessors, its a little hard to not have to think about registers and interrupts.

  • @moonasha
    @moonasha Год назад

    in unity we use these for layer masks. For whatever reason, layers are stored as a series of booleans in a 32 bit (i think) integer... so if we want to mask off layer 7, we have to bit shift 1 over 7 places, 1

    • @alexhyettdev
      @alexhyettdev  Год назад

      That's interesting, thanks for sharing. I have been meaning to try out Unity.

  • @raxmax1421
    @raxmax1421 5 месяцев назад

    very helpful, thank you

  • @dumebiubogu3445
    @dumebiubogu3445 6 месяцев назад

    Thanks for the video. Not sure I am understanding the point of the 2's compliment. Does that give us the answer of ~5 ? So ~5 is -6?

    • @rockingshubzz3201
      @rockingshubzz3201 3 месяца назад

      If you use 2 complement it means ~5 (positive number) will be converted to -5

  • @oreokarail
    @oreokarail Год назад

    Don't stop. There's a long way to go...

    • @alexhyettdev
      @alexhyettdev  Год назад

      Yes it is definitely a long journey!

  • @kevinbatdorf
    @kevinbatdorf Год назад

    What are some common use cases for the last three you mentioned? ~ >

  • @shinkansen1907
    @shinkansen1907 7 дней назад

    thanks

  • @kdt85
    @kdt85 Год назад +1

    what practical uses do the left and right bit shifts have?

    • @alexhyettdev
      @alexhyettdev  Год назад +1

      They do have some mathematical uses.
      Doing x > 5 is equivalent of dividing x by 2 to the power of 5.
      They are also sometimes used for enum definitions which you can see here:
      stackoverflow.com/questions/3999922/why-use-the-bitwise-shift-operator-for-values-in-a-c-enum-definition
      If anyone has any other uses for them, I would be interested to know too!

    • @kdt85
      @kdt85 Год назад

      @@alexhyettdev thanks!

    • @JacksonBockus
      @JacksonBockus 7 месяцев назад

      I use them all the time! Some hardware peripherals will store numerical values in weird places within registers, so to extract them and use them as numbers you need to perform a shift so that each bit is in the right place. Say we had an 8 bit register used by a temperature sensor with the lower three bits being for control and the upper five bits actually representing the temperature. You can extract the temperature by reading the value of the register and doing a left shift by three.

    • @kdt85
      @kdt85 7 месяцев назад

      @@JacksonBockus thank you, yes I've come to realise they are widely used in embedded systems to directly access the pins by manipulating the register.
      Arduino for example used an extraction layer to turn pins on and off, if you use bit wise it's much faster and parallel

  • @nazarinebeats599
    @nazarinebeats599 Год назад

    Im confused, at 4:06 the output is can read, but it looks to me that the result form the bit and should not match so I expected to see 0 ?

    • @alexhyettdev
      @alexhyettdev  Год назад +1

      I don't think I explained that well in this video. As one of the other comments points out (see pinned) for & operator if both bits are 1 then it will equal 1, if both bits are 0 it will equal zero. If they are both different it will be 0.
      So our user permissions are set to 6, which is 110 in binary.
      The read permission is 4 which is 100.
      If you do 110 & 100 you will get 100, which is why you can do:
      if (userPermissions & READ_PERMISSION) == READ_PERMISSION:

  • @hariram5654
    @hariram5654 2 месяца назад

    Respect from INDIA😇

  • @bijjepurushotham7667
    @bijjepurushotham7667 8 месяцев назад

    nice explanation

  • @robertvalentic4939
    @robertvalentic4939 6 дней назад

    also good for networked games

  • @oglothenerd
    @oglothenerd Год назад +1

    I am needing to use them because I am making a voxel game.

    • @alexhyettdev
      @alexhyettdev  Год назад +1

      That’s awesome. I have had “make a game” on my todo list for a long time. One of these days.

    • @oglothenerd
      @oglothenerd Год назад +1

      @@alexhyettdev Highly recommend Rust with the Bevy engine!

    • @SurajAbdullai
      @SurajAbdullai 11 месяцев назад

      @@alexhyettdev Hi pls my account got banned and i need your help

  • @o.fm.a5573
    @o.fm.a5573 Месяц назад +1

    Why is 1 negative and 0 positive? I find it confusing 😅

    • @theEtch
      @theEtch 27 дней назад

      because it's positive by default. the first bit is reserved for that I think.

    • @theEtch
      @theEtch 27 дней назад

      as it's a signed byte

  • @hydrotd
    @hydrotd 8 дней назад

    came for shift

  • @jumbo999614
    @jumbo999614 6 месяцев назад

    Please tech me this code
    Below is part of code that someone wrote for making dot matrix led 8x8 text scrolling
    byte bitmap[8][7];
    int numZones = sizeof(bitmap) / 8; // One Zone refers to one 8 x 8 Matrix ( Group of 8 columns)
    int maxZoneIndex = numZones - 1;
    int numCols = numZones * 8;
    // Converts row and colum to bitmap bit and turn it off/on
    void Plot(int col, int row, bool isOn)
    {
    int zone = col / 8;
    int colBitIndex = x % 8;
    byte colBit = 1

  • @UnknownGamer-lw7zp
    @UnknownGamer-lw7zp 3 месяца назад

    Tq

  • @endribehari6645
    @endribehari6645 3 дня назад

    You can a and b not 6 and 7

  • @realdragon
    @realdragon 11 месяцев назад +13

    I discovered using bitwise operators is faster than dividing by 2 for floats

    • @alexhyettdev
      @alexhyettdev  11 месяцев назад +4

      Good to know! Thanks for sharing.

    • @leonardeuler4
      @leonardeuler4 9 месяцев назад

      Which language?

    • @realdragon
      @realdragon 9 месяцев назад

      @@leonardeuler4 C

    • @Debianguy31
      @Debianguy31 9 месяцев назад

      ​@@leonardeuler4any Language

    • @martinfinch5011
      @martinfinch5011 8 месяцев назад +1

      Also multiplying by 2 using the bit shift left operator is faster as well I believe

  • @seanfull7123
    @seanfull7123 Год назад

    Teach my class plz

    • @alexhyettdev
      @alexhyettdev  Год назад

      Is your teacher not very good, or just boring? 🤣

  • @meerkatpowergaming9412
    @meerkatpowergaming9412 Год назад

    This video is a bit loaded for someone who is truly a beginner.

    • @alexhyettdev
      @alexhyettdev  Год назад

      Noted. I will try and do some more videos for true beginners in the future.

    • @meerkatpowergaming9412
      @meerkatpowergaming9412 Год назад

      @@alexhyettdev Yeah I just find it truly hard to find resources for others on this specific subject. Even 10 years ago.