Java Program to find longest substring without repetition| Amazon coding interview questions

[@narendramodi107]

try this one guys without any additional loops.. HashSet cha=new HashSet(); String Longest=""; String current=""; int j=0; for(int i=0;iLongest.length()) { Longest=current; } }

[@suhaskhot9310]

Oh wow you just changed some lines and got correct code.

[@nekkantisandeepkumar8897]

Thank you so much

[@channelcuriousity6467]

Really i am stucked in solving geeks for geeks. After I solve your 100 basics problem. I have feelings to crack any questions.

[@shankardayal6928]

Thanks for sharing your idea. But in interview I had seen that we had one rule "Don't use any inbuilt methods". Here we use predefined data structure set and its method.

[@premkumareaswaran6875]

As per the problem statement, for the string "abcdablsdh", isn't it expected to return "cdabls" as the result? However, it returns "ablsdh" because during the first iteration of the for-loop, once we reach the second "a" (index 4), we break there and continue with the result of the string. Is this what we are trying to achieve here? Your explanation would be helpful.

[@sauravsemwal7427]

Yes there should be some correction in the code. If we find any repeated character we will delete character upto that character .

[@uttamdey4575]

Hi, one more loop has to be added, the snippet is below for(int j=0;j

[@tharunmanitejakotha5686]

@@uttamdey4575 This words perfectly. The code in the video breaks at a point. Thanks to you Uttam

[@aishwaryajaini9985]

You can try it like this in a more simpler way String str = "abcdablsdh"; HashSet set = new HashSet(); String longestOverall = ""; String longestTillnow = ""; for (int i = 0; i < str.length(); i++) { for (int j = i; j < str.length(); j++) { char c = str.charAt(j); if (set.contains(c)) { break; } set.add(c); longestTillnow += c; } if (longestOverall.length() < longestTillnow.length()) { longestOverall = longestTillnow; } longestTillnow = ""; set.clear(); } return longestOverall;

[@kimyastudios]

@@tharunmanitejakotha5686 it can be done with single for loop also. String s="abacdefb"; HashMap hm=new LinkedHashMap(); int maxLength=0; String maxString=""; for(int i=0; imaxLength) { maxLength=hm.keySet().size(); maxString=hm.keySet().toString(); } } System.out.println(maxString); }

[@Robcuisimplu]

Thank you so much for this videos! You help me get ready for my interview!

[@gkandcurrentaffairs7151]

But we r not getting output

[@lawanutech9977]

Thank you..Keep it up..More power to you👍

[@gsivalingam3980]

Plz display output

[@Bharathkumar-j3a]

sir, for taking user input what i need to do?

[@03_sah]

Sir to find longest substring - all substrings r of same length ,none of them is large- abcd ,bcda ,cdab

[@shenth27]

I haven't tested your code but I think it won't find the correct longest substring in every inputs. e.g. abcdaeb -> bcdae

[@abhisheksrivastava9307]

now worry bro just add one more for loop import java.util.*; class FirstLongestSubstring{ public static void main(String ar[]){ String str="abcdaeb"; String res=Longest(str); System.out.println("Longest Sub-String is :"+res); } private static String Longest(String str) { HashSet set=new HashSet(); String longestOverall=""; String longestTillnow=""; for(int i=0;i

[@shivampathania2607]

This video program not giving any output idk y ? Can anyone help me in this

[@prakashranjan6528]

@@abhisheksrivastava9307 this won't be work still for we cases like. i/p "asjrgapa" o/p should be 6 length as str : sjrgap

[@vijaymaurya3695]

@@abhisheksrivastava9307 even this won't work check for "abcabcbb"

[@ShankyGaming0306]

@@vijaymaurya3695 public class LongestString { public static void main(String[] args) { String str = "abcdaeb"; String finalans = longest(str); System.out.println(finalans); } private static String longest(String str) { HashSet set = new HashSet(); int maxLength = 0; String longestTillnow = ""; String longestoverall = ""; //take each character form the given string for(int i =0; i longestoverall.length()) { longestoverall=longestTillnow; } } //System.out.println("Max Length of longest Substring is " + set.size()); return longestoverall; } } correct ans

[@samrathrdt]

Logic was correct , just did a small improvision. package com.samrat; import java.util.HashSet; // to find substring without repetition public class LongestSubString { public static void main(String[] args) { //String str="abcdabefghi"; String str="dvdf "; String longestSubString = longestSubString(str); System.out.println("String:"+longestSubString); } private static String longestSubString(String str) { HashSet set = new HashSet(); String finalSubString=""; String tempSubString=""; int j=0; for(int i=0;ifinalSubString.length()) { finalSubString=tempSubString; } } return finalSubString; } }

[@prakashranjan6528]

This will won't give correct o/p in case of str = "dvdf"; -> longest would be 'vdf'

[@rahulmundada5268]

Exactly 👍🏻

[@harshitsaluja3809]

This code does not seems to work for "dvdf" the output comes as dv it should come as vdf

[@suprabathj7843]

Good one👍

[@start1learn-n171]

Tq

[@freeebeee7261]

Sir couldn't reach the telegram group ......I assume the link might be expired

[@anjan5545]

For input -> "dvdf" it returns the longest substring as "dv" but it should have been "vdf"

[@Pawan76457]

Yes that's the true answer bcoz that's the longest without repetition

[@ayushsahu3983]

@anjan5545 String str = "dvdf"; String longestSubString = ""; int longestLength = 0; Map map = new LinkedHashMap(); for(int i=0; i longestLength) { longestLength = map.size(); longestSubString = map.keySet().toString(); } } System.out.println(longestSubString); System.out.println(longestLength);

[@dakshinrajavel1064]

It won't work for all String. For example, it won't work for ABADEXED

[@channelcuriousity6467]

Mistake need to add longestoverall+=c

[@Таалай-ж9ч]

Thank you 😊. But why didn't you execute the program?

[@jeevansk3130]

Because it's wrong , it return only first largest substring it will never start to search from i+1 th character , we should do that

[@uttamdey4575]

Hi you are doing a great work really thank you for all these effors from your side. Wanted to ask I was trying with different combination of Strings for eg:- "abacdab" -> the output for this should be cdab but if gives acd. The idea of removing the set and emptying the string inside the loop needs to be modified a bit.

[@springhibernatetutes]

Yes we will check this.Thanks for your valuable comment

[@PainofRiOt]

@@omprakashak7176 a is repeated... common knowledge

[@srivathsansworld4219]

this is not working

[@srinivasand8900]

Longest substring with repeatation..... How to change the existing code sir

[@chsainath6694]

Hi Sandeep, Print the following structure; input =4 1 1 2 1 2 3 1 2 3 4 can you explain this program?

[@arijitmohapatra8737]

For (int i=1;i

[@Luckyupadhyay-c7h]

for(int i = 1; i

[@deepikagupta7864]

This will not work for most of the cases like abadef string..logic is not correct

[@garikapatigopi00]

not applicable for some strings like "dvdf","pwwkew".

[@maheshnaga1862]

Sir u r explaintion is very super I know theory of all java concept but coading section I can fail pls how start coding improvement

[@shankardayal6928]

Same here also before 6 months. I tried to understand logic and implement that without inbuilt methods. Mostly avoid collection as they have many inbuilt methods. This had improved my concept.

[@suhaskhot9310]

There is a loophole in this program. Let me take input as ABCAD so for this input I should get longest substring as BCAD but by this program you won't. You will get CAD as output which is not correct.

[@vinayshah573]

Did you get correct code then?

[@suhaskhot9310]

@@vinayshah573 ya there are many comments with correct answers on this video

[@amans6504]

Ok i understood this completely.. So can you please tell me whether the actual competitive programming is just like this or way harder than this? Asking Just for some motivation.

[@springhibernatetutes]

Harder than this

[@amans6504]

@@springhibernatetutes ok sir I'll try my best

[@MeeraTech_Talks]

Sir without use any method in string se bnao

[@saikrishnasaikrishna9914]

Sir you have to kept link of source code

[@avijitsamanta8784]

Its not work properly

[@rohanchristopher2265]

Microsoft Interview Program : Input KKCCDFC out put should be KK2CC2D1F1C1 , request you create video for this program

[@springhibernatetutes]

Already this program is in playlist

[@chanchalsinghal5973]

Do what u say.

[@sumit1895]

its not accurate

[@vaibhavkove1440]

Please check this and please tell me the my mistake as soon as possible package interview13; import java.util.HashSet; //Ques: Java Program to find longest SubString without Repetition public class LongestString { public static void main(String[] args) { String str = "abcdab"; longest(str); } private static String longest(String str) { HashSet set = new HashSet(); String longestOverall = ""; String longestTillNow = ""; for (int i = 0; i < str.length(); i++) { char c = str.charAt(i); if (set.contains(c)) { longestTillNow = ""; set.clear(); } set.add(c); longestTillNow += c; if (longestTillNow.length() > longestOverall.length()) { longestOverall = longestTillNow; } } return longestOverall; } }

[@saibabukarri6706]

👍🙏❤️👌

[@letsstartagain2430]

I'm not getting you properly 🙄

[@springhibernatetutes]

Watch the video you will understand

[@ananyasamanta9857]

import java.util.*; public class A{ static void function(String str){ String longestTillnow=""; String longestoverall=""; ArrayList l1=new ArrayList(); for(int i=0;i