G-31. Word Ladder - 2 | Optimised Approach for Leetcode

[@takeUforward]

Let's continue the habit of commenting “understood” if you got the entire video. Please give it a like too, you don't 😞 Do follow me on Instagram: striver_79

[@chandannikhil8526]

Bhaiya ek request hai "Evaluate division " wala ques bhi karana pls Ho nahi raha

[@himanshu298]

Baaki log “Google” “Microsoft” ke name pe janta ka kaat te rahengey aur views lete rahengey. But ye banda apni mehnat consistency content quality se ek aisa level set kar jaega, jisse isko aane waali kai generations yaad rakhengi ♥️ Striver in real sense.

[@codingwithanonymous890]

haan bhai true 2024 and 2025 batch ke liye toh gem hain yeh sab...paid course

[@Anicienttimes]

agree

[@artofwrick]

Fantastic approach. I don't see any reason for interviewers to reject such a pretty backtracking algorithm

[@mayurbhor2231]

I find this solution more intuitive than the previous one.

[@sumedhakula7162]

The smart DFS is such an IQ 200 move, Striver, thank you for sharing this with us!

[@anvesh5377]

Two months ago I submitted the python code for this problem and out of 7 submissions, one was accepted with barely 6000+ ms run time, and the others are TLE. But with this algorithm, it gave an average run time of 180ms for python. This much optimized algorithm. Thank you Striver.

[@mohitsingh7793]

As he Said,it will be a cakewalk for a competetive programmer.Just got the goosebumps 😀

[@muditkhanna8164]

this is not a cakewalk(in implementation) for us, probably for understanding its a cakewalk its like a 1600-1800 level question but it could go to 2000 if made some changes like find sequences only in lexicographical order

[@Ahmed_Ataullah]

Following you for the past few months and my problem solving ability has improved quite a lot. Thanks a lot.

[@himadrinath1502]

bhai mena cf pa 2000+ question kar liya Google nikal jai ga na??

[@tanyacse6577]

That's reaally amazing man ❤‍🔥❤‍🔥❤‍🔥 THANK YOU for puting such amazing content , I just want to tell u that I follow your content DSA through out and I get internship in my dream company as a SDE Intern at Amazon. Thank you for putting such a amazing content for freee man really appericatiated 🙌🙌

[@anishkarthik4309]

could share your resume 📄? the one that got your intern at amazon.

[@kaneframe5357]

It might be even better to store vectors of words for each level in an array/vector eg- [0:[hit], 1:[hot], 2:[dot, lot], 3:[dog, log], 4:[cog]]. Then we can go back from cog checking for words on level 3 and seeing if difference in letters is 1. Such a method only compares the words up to 5 time (max no of letters in these words acc to leetcode) instead of 26. It is also faster due to access in array instead of a map. Pretty amazing solution, specially for conservation of memory. Thanks Striver :) Edit: Just realized another thing you can do is build an adj list at the start, which makes the process much simpler.

[@niteshverma8281]

best youtuber for coding in the world ♥🧡🧡🧡🧡🧡🧡♥♥♥♥♥♥♥♥

[@Dontpushyour_luck]

First time I tried this problem, I did think of extending on the word ladder 1 concept by first calculating minimum seq length and then checking all sequences upto that length, probably that would have given me tle, this is a nice approach.

[@subodhkasaudhaniitk796]

Yes that gave TLE

[@Health_asset]

I found this method best in between these two videos , first one was confusing , thanks striver sir

[@shivankshukla2519]

is this the end of this course. The way you make things easier is amazing. I THANK you for such helpful content creation, in every success of mine you are a great contributor.

[@SaquibAnsariofficial01]

As a Competitive Programmer I find this solution the more concise and easiest though that dfs was really awesome

[@imPriyansh77]

Yeah

[@parallax8916]

Dude, I coded it myself after watching haldf of the vdeo and I found out the error u were talking about in 1 go!!! Thank u soo much bro for explaining soo tough problem in such a simple way!!!

[@codinghustler6771]

Hey striver, first thank you for creating such great series for us. We love you so much. Because this is a graph series so we can discover a graph way of solving this problem. Convert the input into a unit weight undirected graph and then we will be able to find the solution using all paths using dfs solution. I have checked that by running on leetcode. Again thank you so much guruji.

[@jayant-baid]

Can you please send the solution

[@artistyashwardhan8995]

after reading your comment i thought about this and came up solution, but this is giving TLE, it will be great help if you can share your solution. class Solution { unordered_map mpp; vector ans; string ew; private: void dfs(string word, unordered_map adj, vector& seq){ if(word == ew){ if(ans.size() == 0){ ans.push_back(seq); }else if(ans[0].size() >= seq.size()){ if(ans[0].size()>seq.size()){ ans.clear(); } ans.push_back(seq); } return; } for(auto it: adj[word]){ if(mpp[word] + 1

[@TrendyGamer007]

this is real content and that tooo for free..... striver can you make a compitative programming playlist from beginner level to advanced just like this one .... can't find any on youtube🙂

[@sonit9707]

The thing about cp is you will never find similar patterns of problems like you do on leetcode.

[@lakshsinghania]

@@sonit9707 true

[@lakshsinghania]

u need to explore yourself by trying out lot lot lot of problems on cf,cc,sj etc and learning tricks for solving them

[@prayasgautam9595]

This ain't no hack...you just need to be too smart to pull it off. Hats off Striver !!!!!!!!!!!

[@noobCoder26]

thanks Striver , I am learning the whole Graph from your awsome series ✨✨

[@dhruvsolanki4473]

Very amazing explanation.

[@neymarfan4023]

Bro now way I am solving this question in a 45 min interview using this techinque lol. Altho I might as well learn for cp

[@AshwinHarish-u4t]

Thank you for the great explanation sir Sir, can you please tell me why this approach should not be used in interview??

[@akshayanm]

I've never seen a question like this before. It feels great to submit this solution

[@pulkitgupta669]

Thanks Striver. Understood. I have recently started competetive programming so I want to understand this approach. I am learning a lot.

[@atulwadhwa192]

Surely deserve a like on this brilliant explanation tho I'm not in cp much but understood every bit of it.

[@stith_pragya]

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

[@idlegaming1]

this approach is easy understandable then previous one

[@yashshukla1637]

really great concept. must know for your google interviews.

[@pulkitjain5159]

amazing approach , found new way of approaching a problem. Thank you Bhaiya!!

[@tejpratap9051]

Hey striver, when will you upload the next set of videos, I'm eagerly waiting.

[@Ankit.yt_885]

Bhaiya Amazing content ! Baaki ki videos kab tak upload hojaegi can you please tell an expected date?

[@coding8000]

I am ready to help and die for you till my last breath, you are my man

[@saranghae3720]

U never failed to amaze me 🌻 P.S Just Striver things

[@TechieClasher]

Hey striver, The link to this video is not given in the atoz sheet, the world ladder I video link itself is given for word ladder II video. Thanks for the content.

[@cinime]

Understood! Another super amazing explanation as always, thank you very much!!

[@crazyduniya128]

ohhh!! mera to dimag hi hil gya 🤯🤯

[@ashutoshanandsharma007]

Waiting for the new videos of this series❤. I hope you will upload them soon.

[@appleinc.2325]

love you sir, you are the real saver for us. 🤩🤩

[@Rajat_maurya]

Any update for videos delay bhaiya?

[@dhirajsonawane3720]

sir ji sabse jyada wait apke next video ka horaha hain. I hope it will come soon

[@Werewolf5684]

I would not recomend to skip this, specially when you are preparing for Goolge

[@visheshkaran7083]

Understood😇

[@gsmdfaheem]

Bhaiya new videos kab aayengi? Eagerly waiting....

[@gangsta_coder_12]

Understood 🔥🔥🔥

[@anandA3b]

this was actually easier than the first approach

[@imPriyansh77]

yes, & the logic of starting from endWord towards the beginWord is also helpful..

[@Saurav_Kumar514]

Just Wow 🔥🔥

[@bhanupratapsharma6158]

bhaiya iske baad next series kiska hoga toda cp ka bhi topic daal do segment tree ya cp sheet which help alot

[@vikaskumar5066]

Ha bhaiya

[@vikaskumar5066]

Jaise cp sheet

[@vikaskumar5066]

Ya string suffix

[@aadipaadi9146]

Ha bhaiya cp sheet yaha to samjh aa jata leetcode ke vhi ho jaate hai magar codeforces ke nahi hote Phir problem aati hai cp sheet

[@rinaksharma7596]

Cp sheet is best in which topics with question are seperated

[@balakrishnanr648]

understood, but please say the time and space complexity also. Is it O(N*M*26)

[@Yash-uk8ib]

Sir, for dfs part, instead of changing character, u could have simply traversed 9n decreasing min value... again saving time and space.

[@chinthalatejeswarreddy1026]

In the base case of recursive function dfs we need to add a condition that what ever the sequence that we are getting it has to be the same length of the sequence that we had at the first sequence in the ans vector

[@imPriyansh77]

No, it's not required, we are adding elements in seq vector only when they are present in the map & are of one small level than the word from which they have been transformed

[@shivam-shah]

Correct me if I am wrong but isn't this question using dynamic programming in graph and using the same technique like printing the longest increasing subsequence problem in DP .

[@lucygaming9726]

I thought so too. Looks exactly like LIS, but here we are not simply decrementing level and iterating over map.

[@ITSuyashTiwari]

i loved the solution

[@guptafactory]

Instead of reversing the Sequence vectors in last DFS call, we can reverse it just before return of Ans. for(vector &vec : ans) reverse(vec.begin(), vec.end()); return ans;

[@beinghappy9223]

In C++ it is always private by default , why do you write private everytime ? Is it related to some good code practices?

[@imPriyansh77]

Yes, you're right that private is by default. He is writing private, as he is showing how to write a code in an interview. Writing industry level codes in interview is good

[@tanaysingh5348]

can't praise you enough

[@Chandraprakash-kx4ic]

step_1 time 2:08 step_2 time - 5:46 why did this code run and not the previous - 11:32

[@vaibhavagarwal2421]

this is more intuitive to me than storing vector of strings in a queue

[@imPriyansh77]

Yeah

[@aaaaz424]

Striver! I have a genuine question. I am a working professional. What is the upside of doing competitive programming for those who are already working? Should I focus more in development ?

[@UECAshutoshKumar]

Thank you sir 🙏

[@vakhariyajay2224]

Thank you very much. You are a genius.

[@ritikshrivastava9442]

one question = while erasing we are checking if(st.count(word)) means the word should be present then only erase, let's say we erased endWord, and now for calling dfs we are checking endword should be present if we have already erased it while pushing how it can be present beginWord = "hit", endWord = "cog", wordList = ["hot","dot","dog","lot","log","cog"] do dry run for this

[@VishaliniT-f3g]

Understood 😊

[@abhishek__anand__]

Great Explanation

[@mrtuyiop]

What if we wanted to wanted to find only one possible combination in best space complexity

[@AbhavGoel]

in the dfs fucntion cant we iterate over the map and look for the words with one step less than current word and apply dfs on them. It would reduce the computations for trying all words in the dfs

[@lucygaming9726]

We can't because we have to figure out the right sequence. Look at the example he gave and try this once.

[@Rajat_maurya]

Sir code not working only 32 out of 36 test case are passing?

[@RitikRaj-we2sc]

i am not able to understand one thing, that why previous solution gave TLE, because there too we were trying all the possible combination of word, and same is being done here. Someone please explain this.

[@ApoorvBedmutha]

This guy is my god

[@noobCoder26]

i dont know why I felt this approach slightly easier than earlier 🎃🎃

[@GyaanGrave]

preparing for interviews only but still watched it out of greed for problem solving ability even after you telling not to watch it 😎

[@rachit2982]

Please make a video solution on word wrap problem given on gfg and please explain both solutions (space optimised and brute force)

[@NARUTOUZUMAKI-bk4nx]

understood class Solution { public: map mp; void dfs(string endWord,string beginWord, vector &vec,vector &vs){ if(endWord==beginWord){ reverse(vs.begin(),vs.end()); vec.push_back(vs); reverse(vs.begin(),vs.end()); return; } for(int j=0;j

[@sanjayp.m7008]

This one seems more intutive for me, but y shld i not say this in interviews?

[@piyushgoel3020]

thank you striver

[@suryakiran2970]

Understood❤

[@The_Shubham_Soni]

UNDERSTOOD.

[@anonymous-ms2en]

@Striver bhaiya os,dbms and oops topics ki bhi playlist bna do plzz

[@vaarigupta6332]

I think that the optimized approach is better than this one. This seem to be bit complicated but the optimized approach seems to be an extension of word ladder 1 so that seems to be good approach than this one.

[@prathamsharma4416]

Striver, a big W

[@p38_amankuldeep75]

understood❤❤❤

[@suhasdevang9332]

striver brother pls make a video about when the top tech company hiring start in 2022 and some tips to get shortlisted... please brother

[@sakshisinghal1669]

Hey @Striver can you also cover floyd warshall?

[@takeUforward]

I will.

[@Learnprogramming-q7f]

Thank you bhaiya

[@ADITYAKUMAR-tb4gm]

understood

[@madhurgupta4220]

Understood !

[@bhavya8608]

understoodd!!!

[@nishantdhamija2880]

Understood how many more videos of this series

[@HimanshuGupta-ni3pk]

Yeh kon sa series ka hai ?

[@nishantdhamija2880]

@@HimanshuGupta-ni3pk graph

[@krishanpratap3286]

Maja aa gaya bhayiya us*3

[@ayushjain386]

Next videos kb aari hai ?

[@gametech7046]

Bhaiya union find pe videos nahi aengi kya? Mene A-Z sheet check kiya lekin usme Union Find covered nahi hai 😔

[@harshdasila6680]

bhaiya saari videos aa gyi h ya abhi aur baki h??

[@valarmorghulis9244]

Bro Can we not show this solution in an interview. It seems to be more easily explainable then the previous one.

[@vishichaurasiya4427]

15:08

[@edu3956]

What's happen? Why not uploading bro?

[@GauravKumar-by1yt]

Understood

[@KratosProton]

great

[@ashutosh..]

What's the cp thing in this?

[@yashshukla1637]

One notes added

[@amiteshshekhar601]

when will you start uploading videos for dsa from starting