Longest Substring Without Repeating Characters | Leetcode 3 | Sliding window

[@jasper5016]

Thanks. Here is the Java code if someone needs it - public int maxSubString(String s) { int[] count = new int[256]; int l = 0; int r = 0; int ans = 0; while (r < s.length()) { char currChar = s.charAt(r); count[currChar]++; while (count[currChar] > 1) { count[s.charAt(l)]--; l++; } ans = Math.max(ans, r - l + 1); r++; } return ans; }

[@AyushiSharmaDSA]

thank you for sharing your code and helping others :)

[@azhargayawi]

after wasting approx 5 hours on you tube i found the genuine logic here, thank you mam. greaat....

[@AyushiSharmaDSA]

glad it was helpful :)

[@cs_soldier5292]

This can help someone :) class Solution { public: int lengthOfLongestSubstring(string s) { //creating a set to store the list unordered_set ans; int value=0; int i=0,j=0; while(i

[@RajeshS-n2j]

well explained solution, in particular I like your making use of blackboard to go over approach to solution first, helps us a lot. 😀

[@AyushiSharmaDSA]

thank you 🤗

[@venkatvasamsetti8125]

I have already done this problem using hashmap.but without sliding window.thank you for this optimization of code

[@AyushiSharmaDSA]

Welcome Venkat, glad it was helpful :)

[@shinosukenohara.123]

can u explain your hashmap approach ?

[@harshvardhan7762]

for java coders, there will be slight changes:- public int lengthOfLongestSubstring(String s) { int[] arr = new int[128]; int n = s.length(); int len = 0; for(int i = 0, j = 0; j < n; j++){ int c = s.charAt(j); arr[c]++; if(arr[c] > 1){ while(arr[c] > 1){ arr[s.charAt(i)]--; i++; } } len = Math.max(len, j - i + 1); } return len; }

[@coding619]

Good explanation but I guess the space complexity mentioned in the description should be O(k), where k are the unique characters and not O(1).

[@FootB_shorts1]

After wasting a lot of time i found A helpful video . thanks❤❤

[@AyushiSharmaDSA]

welcome, glad u found it helpful :)

[@ashjournal]

Waiting for Chennai vlog part 2 😍

[@AyushiSharmaDSA]

❤️❤️🙌🏻☺️

[@BADASSBLADE]

Solve Today's Leetcode Challenge(Erasure Problem,) by using this approach, thankyou keep up the good work

[@AyushiSharmaDSA]

Thanks ☺️

[@ankitris5201]

crystal clear explanation mam 👍👍

[@AyushiSharmaDSA]

thank you :)

[@samyakagarwal1777]

very well explained ...........100/100

[@AyushiSharmaDSA]

thank you :)

[@luckilygamer5462]

int lengthOfLongestSubstring(string s) { unordered_map umap; int n = s.length(); int ans=0; int start=0; for (int i = 0; i < n; i++) { if(umap.find(s[i])!=umap.end()){ // update the start index to the next character after the last occurrence start = max(start, umap[s[i]] + 1); } umap[s[i]] = i; ans=max(ans,i-start+1); } return ans; }

[@Darshan-p5r5k]

hi aushi, using two while loop may increase time complexity else we can use hash map for storing index of characters

[@jaikrishnapandey632]

Great explanation

[@AyushiSharmaDSA]

Thanks Jai :)

[@arqamazmi3327]

Nice Explanation Try this also. Longest Repeating Character Replacement

[@AyushiSharmaDSA]

Thanks, sure 😊

[@kishorjanjal7454]

Thank for crisp solution 😌😌

[@AyushiSharmaDSA]

Welcome Kishor, glad it was helpful 😊

[@knixkcodes]

very well explained!

[@AyushiSharmaDSA]

Thank you , Glad it was helpful!

[@restless4263]

nice explanation

[@AyushiSharmaDSA]

thank you, glad you liked it :)

[@priyankakataria7922]

Time complexity worst case will be O(n^2) right? Coz two while loops

[@dhanrajlouvanshi7872]

i am waiting for this

[@AyushiSharmaDSA]

Thanks Dhanraj :)

[@aman_kumar0208]

Thanks di

[@AyushiSharmaDSA]

Welcome Aman 😊

[@SuryajyotiDas]

thanks ma'am

[@AyushiSharmaDSA]

Welcome 🤗

[@deeptimayeemaharana2448]

You're best😁

[@AyushiSharmaDSA]

Thanks Deeptimayee 😊

[@abhishekprasad7568]

Di should i buy coding ninja dsa course or study from free resource . pls response

[@AyushiSharmaDSA]

The course is good and you can learn from free resources also, so it totally depends on you :)

[@bibs24]

Thanks a ton!

[@AyushiSharmaDSA]

Welcome :)

[@ashjournal]

👍👍

[@AyushiSharmaDSA]

😊😊

[@jagmohangautam1062]

it is giving runtime error for string containing space

[@UdayGarg]

thanks ]

[@AyushiSharmaDSA]

welcome :)

[@ModestShalini]

Can we take char array of 128 size??

[@pratiksuman007]

​ @AyushiSharmaDSA Your solution seems better then what available in general platform. What resource you have used to train yourself, could u make a video of it or if already there then link pls?

[@abhisheknavhal1039]

The solution for the test case 'pwwkew' is not giving the correct answer.

[@bellanatrisha1201]

how is taking count[a] ?

[@vinaykulkarni8863]

int lengthOfLongestSubstring(string s) { unordered_mapmp; int i=0,j=0,ans=0; int n=s.length(); while(j1){ mp[s[i]]--; i++; } ans=max(ans,j-i+1); j++; } return ans; } };

[@umang1226]

please make in hindi we are more comfortable in it .

[@Srihan_kumar]

In gfg this code is not working

[@NikhilKumar-br4nj]

Didi if possible pls give java code also

[@amitsinha806]

👍👍👍👍👍👍👍👍👍👍👍👍👍👍

[@AyushiSharmaDSA]

Thanks Amit :)

[@akashonlinehere]

that code gives wrong ans in leetcode

[@vamsiv5767]

This code gives wrong answer for aabccbb

[@sumitpal9113]

Java code is not working in testcase "pwwkew". can any one help me. public int lengthOfLongestSubstring(String s) { int count[] = new int[256]; int maxLen = 0, i=0, j=0; while(j < s.length()){ int index = s.charAt(j); count[index]++; while(count[index] > 1){ count[index]--; i++; } maxLen = Math.max(maxLen,( j-i)+1); j++; } return maxLen; }

[@mohammedafreed9741]

In second while loop it's count[s.charAt(i)] not index. And why are you taking extra variable index

[@abhisheknavhal1039]

This solution is not working for pwwkew case

[@harshvardhan7762]

@@abhisheknavhal1039 in line 8, it will be ************** count[s.charAt(i)]--; ******************************will be there

[@CoDestination]

Hindi Java kzbin.info/www/bejne/nniVd5pse9GFd5Isi=DlUeAE29pJsP5viX

[@AtharvVyas-y8w]

You could've just took i and j. Why did you made it look difficult. We are beginners that's why we are here watching your videos. Please take care of it next time. Nice Explanation tho

[@softwareengineering101]

Nice explanation

[@SAHIL-jm2hv]

Thanks ma'am

[@AyushiSharmaDSA]

Most welcome 😊

[@KunalKashyap6]

thanku di

[@AyushiSharmaDSA]

Welcome Kunal :)