L2. Must Know Tricks in Bit Manipulation | Swap two numbers without third variable

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[@modiji8706]

1. Swap two numbers - 00:00 2. Check if ith bit is set or not - 3:47 3. set ith Bit - 10:47 4. clear ith Bit - 14:27 5. Toggle ith Bit - 17:52 6.Remove the last set Bit - 21:23 7. Check if a number is power of 2 or not - 28:26 8.count the number of set bits - 31:24

[@NAMAN-wj7dj]

thanku modi ji ! abki baar 400 paar 👍

[@modiji8706]

@@NAMAN-wj7dj Vote dena mt bhulna Abki baar Modi Sarkar

[@02deepak]

@@modiji8706 modi ji wo recession ka kuch hojata toh badhiya maan lgta voting m

[@himanshutiwari6614]

​@@02deepakmodiji khud pdh rhe hai dsa😅

[@modiji8706]

RastraPati Bhawan ma A jao kl ispe wartalap krte hai

[@Noob_Coder1234]

REMEMBER IF STRIVER IS MAKING , THEN IT WILL BE THE BEST PLAYLIST ON BIT MANIPULATION

[@siddiqabr7110]

Have you ever watched kunal kushwaha's videos

[@aayambhatt5363]

@@siddiqabr7110 his videos arent any good

[@mayankagarwal6775]

@@aayambhatt5363 yes !! I had started my dsa journey from kunal but now shifted to striver after understanding basics of dsa.

[@lillyput2275]

@@aayambhatt5363I don’t understand his way of teaching

[@CDK-Tech]

@@aayambhatt5363 His videos was once good , now it's not 😭

[@fazfavas-d6j]

Never seen better teacher than u

[@Benstokes555]

YESS

[@raorao7329]

true

[@roshankumar280]

One-Liner: 1) Swapping Two Numbers : Num1=(Num1^Num2); Num2=(Num1^Num2); Num1=(Num1^Num2); 2) Check If i’th bit is set or not: if((Num&(1

[@Monjaverse]

Love you bro ❤❤❤

[@nguyengiahuy6292]

struggling so much with this topic alone. Thank you for the series!!!!

[@uzzal.cse42]

Crystal clear explanation. Highly recommended for those who does not know anything about bit manipulation.

[@SumitKumar-qg4ps]

to clear ith bit(0 indexed), we can just do N = n xor (1

[@chickukoshti3741]

toggle

[@AnushkaMishra8]

Yes , but it will work same as toggling if the bit is not set and we don't want that , if the bit will be 0 then also it will be changed to 1 if we do this.

[@HaamroNotes]

@@AnushkaMishra8 yeah bro

[@SuvradipDasPhotographyOfficial]

Awesome Striver, done with sliding window and two pointers and now started with bit manipulation yesterday

[@AdityaSharma-er3gs]

33:00 here you can simply do this public static int countSetBit(int num){ int count = 0; int one = 1; while(num > 0){ if((num & one) == 1){ count++; } num = num >> 1; } return count; }

[@priyanshugupta7840]

it is almost the same thing taking the same time except you create one more variable num ;)

[@udayshankar-e6v]

Many times I thought to comment on his post and lastly just leaving it by pressing like button.. thinking that kya kya bolega log,,! Is there anyone else like me ? Aisa koi h Banda Jo striver se bhi accha padhata ho ! I don't think so some one exist ❤

[@pranavmittal9619]

ek h lekin me nahi batunga bas hint de deta hu : 2 crore ka package chod diya bande ne

[@udayshankar-e6v]

​@@pranavmittal9619Bhai hai to bata do jara hum bhi Jane kon h, teacher hi na , terrorist thode h Jo bata na paoge 😂 kahi tum hi to nahi ho wo 2 cr vala Banda Jo chhup chup ke bit manipulation ka maja le rahe ho😊

[@raorao7329]

@@pranavmittal9619 who??

[@pranavmittal9619]

@@raorao7329 bhai coder army wale rohit negi bhaiya hai hindi lanuage ke liye bas striver best hai lekin Full english me concept grasp karne me dikkat bhi aati hai or striver ka code high level ka rehta hai or rohit negi ka low level ka code lekin output same rehta

[@tgayush1424]

amazing video covering all concepts, soon will be mastering bit manipulations by completing your playlist.Before i used to be scared of seeing bits but now it's easy , even i started to use , today i used in one question and solved that question easily.

[@codingp110]

Best Bit Manipulation tutorial ever!!!

[@knowthrvdo]

Thanks for starting uploading again it is very helpful for us.

[@bhushandharne8827]

Sir, Your Techniques are superb

[@ankushrai3155]

the efforts this guy puts is just amazing

[@KaushalDhruw]

before this I thought I knew bitwise operations. But the tricks you've shown are awesome. Thanks again.

[@tamannaverma4178]

Thanks for all these efforts :)

[@ce038_divanshsingh3]

i just stuck to your glow in comment section 😂😂 , forgot about the lecture that is running in the background ..

[@Karanssharma03]

i dont know how to say thank you but you saved me striver . thank you>3000

[@coderspathway]

I have paid DSA course from GFG. But not able to understand BIT manipulation. After watching this playlist by striver I feel the striver did it better than any other paid course in the market.

[@Thinker-360]

same here i paid for my gfg self paced but i'm now watching strivers youtube to solve DSA

[@harshverma9675]

Bhai aapka knowledge toh kamal ka hai bhai.

[@kbsce]

Neatly, clearly explained which anyone can easily understand 😊really appreciated your efforts😊

[@rishavjain5087]

This is just too good to be true bro.. Thanks a lot❤

[@momentcoder]

The best teacher for dsa 🔥🔥

[@stith_pragya]

Understood....Thank You So Much for this wonderful video.........🙏🏻🙏🏻🙏🏻🙏🏻🙏🏻🙏🏻

[@rahuljain224]

Salute to your hardwork and explanation

[@leaguesonu9354]

hats off man for your hardwork

[@TejeshReddyThippakkagari]

Thanks for teaching every possibility answer for the problems❤❤❤

[@SamirKumarRakshit-c4z]

int count = 0; int num = 7; while(num > 0){ num = (num & (num-1)); ++count; } print(count) We can also do this in order to count the set bit (1)😊

[@JIHYELEE-h2m]

Wow this is essence of bit manipulation!!!!!!!!!! Thank you so much

[@lakshmanlk977]

Ohh striver such an amazing lecture ..

[@ishwarreddy8820]

If striver is making then it will be the best playlist ;

[@SaswataMaitra]

17:20 another approach (n&(INT_MAX^(1

[@rohan8758]

*java code* Set ith bit from last, conside 0 based indexing (10:47 ): public static void main(String[] args) { int n = 9; int k = 2; int second_desired_num = 1

[@veerverma5586]

Keep going 🏆

[@akashddeepchitransh4537]

Knowledge Packed Lecture.

[@Benstokes555]

MY MAN IS BACKKKKKKKKKK

[@KapilSharma56419]

there is a question on GFG : Count total set bits You are given a number N. Find the total count of set bits for all numbers from 1 to N(both inclusive). which shows TLE by all your methods can you please explain it .

[@andrewcenteno3462]

This course was insanely good

[@itxamanpanwar8556]

🙏🙏TQ bhaiya for such a good explanation is topic ma smj hi ni aa raaha tha ab sb easy lg r ha

[@sakshikatiyar5353]

u are the best teacher

[@DeepakKumar-nq4td]

Hila diye bhaiya ji 🎉🎉🎉❤❤

[@tapasyadimree9651]

17:20 when finding ~(1

[@GoluKumar-sb2si]

same doubt bro

[@AkOp-bf9vm]

i think we cannot access 2's complement part and can only access negated part of the number maybe i am not sure

[@CodeByRobin]

same doubt bro ,, I raised this on lecture one as well, but bhaiya is not replying....

[@padduchennamsetti6516]

understood ,thanks alot

[@utkarshtiwari7500]

To clear ith bit we can do :- return ( n ^ (1

[@shivanshpatel1898]

no we cant because 0 ^ 1 is 1 so if ith bit is already zero it will change it to 1

[@JunaidhFardeen]

It is for toggle

[@anshrathore2731]

Thank you so much BHAIYA 🙏🙏🙏

[@ryugagaming195]

Sir plz make more videos on sliding window

[@ShravanKumar-wg9pv]

W lecture. Thank you very much sir.

[@rithish993]

17:30 instead we can left shift 1 and use xor operators

[@UECAshutoshKumar]

Thank you sir 🙏

[@nashalafroz]

17:30 sir if we use not operator wouldnt the number converted into its 2's complement

[@janarddansarkar2694]

same doubt. Someone please clearify

[@janarddansarkar2694]

What I am assuming is since we are not storing the negative answer, so 2's complement is not used. If the answer was negative, then to store it, 2's complement would have been used. This is my assumption though. Not sure

[@human0225]

Any solution to this I am still struggling with this.

[@kumarnishantnitallahabad160]

same doubt

[@CodeByRobin]

Same doubt .. You got the answer.

[@ganeshjaggineni4097]

NICE SUPER EXCELLENT MOTIVATED

[@SHINGAVIKAJAL]

super amazing!!

[@Josuke217]

Great lecture.

[@PavanKumar-jz5ow]

UNDERSTOOD 🎉🎉😁😁😁😁

[@riachoudhary__]

Thank you for making this video

[@rahulpatil2472]

for each problem if you write code that will better, but you already created playlist

[@MuraliVardhan-s4s]

thank you anna🧡

[@CodewithAnuragBassu]

Thanku so much bhaiya❤❤🙏🙏🙏🙏

[@DeepakPatel-d5v]

Thanks a lot Bhaiya

[@edsongeorgerebello547]

In the clearing the set bit won't the negation of the left shift 1 make it a 2's complement and the program will add a 1 to it ?

[@banothutharun2743]

simple superb sir

[@vijeshsshetty]

thank you sir ji

[@karthik-varma-1579]

Set> Or Clear/Remove -> And Toggle -> Xor

[@aryansinha1818]

38:00 around, using the last method

[@uditgarg6508]

for checking ith bit set just do right shift by ith and check the resukting num is odd. if it is , it is set. else , not ...

[@ReNaq313]

39:00 -> repeatedly removing the rightmost set bits and taking the count of times we did this operation would give us the number of set bits in a number

[@CodeByRobin]

somewhere in the comments , i read "computer store binary as flipped but while showing us it do 2's complement to show us -ve binary in interger" is this right?

[@cleweric]

in case of power of 2, n & (n-1) == 0 will not work if n = 0, as 0 is not a power of two, we can rather use n & (-n) == n, which mean AND n with its 2's complement it would result n, if its a power of 2

[@thaman701]

Great sir.❤

[@gayathripamarthi8451]

That end music !!!

[@Sahilkumar-hj4vm]

at 17:30 striver do the NOT operator and it flipped all the bits making it a negative number then according to full NOT operator it do 2's complement also but striver stopped at flipping can someone explain me why? edited - ok i get it why computer store binary as flipped but while showing us it do 2's complement to show us -ve binary in interger

[@Sonu.Singh.28]

If you find the swapping using xor confusing, then instead of xor operation use the addition and subtraction operation, it will do the job. a = 17 b = 27 a = a + b # a becomes 17 + 27 = 44 b = a - b # b becomes (17 + 27) - 27 = 44 - 27 = 17 a = a - b # a becomes (17 + 27) - 17 = 27

[@anantmishra5174]

I HAVE ONE QUESTION WHEN WE ARE CHECKING IF I'th BIT IS SET OR NOT WHILE DOING RIGHT SHIFT OF NUMBER (n-1) TIMES. WOULDN'T IT CHANGES THE INPUT NUMBER SUPPLIED.

[@Neo-mx2yf]

So in prev video, a method was taught to find ~x but it is a bit unclear. Let me try clear it up. Actually, ~x is just 1's complement of x, i.e., flip all bits. Eg: ~19 = ~(010011) = (101100) in binary = -20 in decimal Now we know (-x) is actually 2's complement of x. So what he taught is actually to find -x manually. Take prev eg, ~(010011) = (101100) in binary = -(2's complement of 101100) in decimal = -(010100) in decimal = -20 Take other way, ~(-20) = ~(101100)=010011 in binary=(directly) 19 Note: For easiness just assume that instead of 32 bits, there are only 6 bits here.

[@mahaboobpeershaik658]

Can we get slides notes, @takeUforward bro?

[@music-loverFam]

Understood😊

[@LemesaElias]

In python you can swap without using a 3rd variable like a , b = b , a

[@Phantomex984]

u can do swap without using 3rd var in all languages just use a = 3, b = 7, b+=a, a = b-a, b = b-a, Output : , a = 7, b = 3,

[@k.k.harjeeth5422]

unset the right most set bit : n&(n-1) set the right most unset bit : n | (n+1)

[@abhinavraj6507]

At 17:20 striver is not taking 2's complement for NOT operator ? Last video he taught that if after flipping the number becomes negative , we take 2's complement , anyone please help ?

[@CodeByRobin]

same doubt. Please let me know, if you got the answer

[@Mohd-12335]

we can swap without using xor ? a = a + b; b = a - b; a = a - b;

[@ansariaburehan263]

Love it.

[@aayushgakhar3525]

in clearing the ith bit ques shouldnt we take -1 as while finding not of 1 its sign bit also changes in first step and so it becomes -ve and so we have to find its 2s compli

[@CodeByRobin]

same doubt bro,, if you got the answer. Pease reply

[@DeadPoolx1712]

UNDERSTOOD;

[@Learnprogramming-q7f]

Thank you Bhaiya

[@akshatchoudhary2783]

Bhaiya in the Clear bit Soluton can we use XOR operation? like below n = 13, i =2 13 -> 1101 1

[@CodeByRobin]

use an example where the ith bit is already 0. You will get to know

[@kingraj4797]

I think right and left shift operation or not required for finding the i th bit is set(1) or reset(0) for given binary digits Here I have code please verify it it is taking O(1) time complexity to find it.. // ith bit is set or reset import java.util.*; class SetOrReset{ public static void main(String args[]) { Scanner sc=new Scanner(System.in); String str=sc.next(); int i=1; int j=str.length()-1; int x=str.charAt(j-i)-'0'; if(x==1){ System.out.println("Set"); }else{ System.out.println("Reset"); } } }

[@shashankgsharma0901]

Understood!

[@sachinvarma9949]

Bro loves 13 anyways best lecture on yt.

[@amanasrani6405]

Amazinngggggggggg❤

[@yash30095]

understood!

[@ifirdaus0_0]

can i use (n ^ (1

[@aayushgupta7839]

yes you can , I have also done the same for the code ninja question and it cleared all the test cases.

[@coder_07]

Yes , but it will work same as toggling if the bit is not set and we don't want that , if the bit will be 0 then also it will be changed to 1 if we do this.

[@chirag71269]

STRIVER 🤩

[@ok-jg9jb]

Thanks❤

[@swaroopvengali]

Python 1 liners- ============= Swapping two numbers: a = a ^ b; b = a ^ b; a = a ^ b Check if i'th bit is set or not: print("SET" if (Num & (1

[@mordernmonk194]

One-Liner: 1) Swapping Two Numbers : Num1=(Num1^Num2); Num2=(Num1^Num2); Num1=(Num1^Num2); 0000101 = num1 ^0001001 = num2 ________ 0001100 xor of num1 and num2 stored in num1 0001001 = num2 ----- 0000101 xor of (num1 and num2) and num2 stored in num2 0001100 ----- 0001001 2) Check If i’th bit is set or not: if (( Num &(1

[@TechieClasher]

Helpfull

[@KartikeyTT]

tysm sir

[@kalkeshvyas7897]

great

[@rahulnagwanshi2348]

check if a number is a power of two -> !(N & 1)

[@riddhithbanerjee]

In the power of 2 case...what if the number is 0 or INT_MIN then for 0 it will be n&n-1 = 0&-1 means 0...0000 & 1...1111 its coming 0 then it will return true but actually its not power of 2 And in case of INT_MIN n&n-1 the n-1 value is getting overflowed...please solve the doubt anyone.