Print Encodings - Solution | Recursion | Data Structure and Algorithms in JAVA

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NADOS also enables doubt support, career opportunities and contests besides free of charge content for learning. In this video, we discuss the solution of the Print Encodings problem where we are required to print all the strings of alphabets according to the input given as numbers where every alphabet is assigned a value of an integer. To understand the problem statement clearly, click here:
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[@chopchop17]

code in c++ with slightly different approach: #include using namespace std; void pencod(string s, string ans) { if (s.length()==0) { cout

[@nandinisharma5495]

thanks buddy for the code

[@anjulatakashyap6974]

One of the best teacher i have ever seen.

[@Pepcoding]

Glad to know that you liked the content and thank you for appreciating. The love and respect which I get from you people keep me highly motivated and the same I am able to forward It to you people through my videos. So, keep motivating, keep learning and keep loving Pepcoding😊

[@yoyo8293]

Sir apka code thoda complicated hogaya , maine call smart ,base case normal approach lagaya aur accept hogaya : - public static void encodings(String que,String ans,char[] alpha) { if(que.length()==0) { System.out.println(ans); return ; } char ch=que.charAt(0); if(ch=='0') { return ; } char smallAns=alpha[ch-'0']; String ros=que.substring(1); encodings(ros,ans+smallAns,alpha); if(que.length()>=2) { String idx=que.substring(0,2); int index=10*(idx.charAt(0)-'0'); if(index==0) { return ; } index+=(idx.charAt(1)-'0'); if(index

[@pankajbisht897]

HI Summet it would be of immense help if you could state the brute force approach. Maybe for some questions brute force could help to get to an optimum sution

[@vasudevparmar9876]

Just like key pad combinations video, we can define global variable here to It will reduce the code

[@prabhsharansingh3805]

bro means if we change a,b,c instead of keypad then we don't have to check for ques.length() for 1 and 2? and we can simply apply the keypad code with required changes ?

[@raj_kundalia]

Watched on 22 Nov, 2021 - Thanks for the video.

[@Pepcoding]

Hope you like the video for better experience and well-organised content visit on nados.pepcoding.com. Also you can post your query on Community tab. Don't forget to follow us on Instagram instagram.com/pepcoding/

[@pratyush__agarwal]

Very well explained ❤️

[@Pepcoding]

Thankyou!

[@aashishgoyal1436]

thanks a lot Sir for explaining the soln in easy to understand manner

[@Pepcoding]

You are most welcome

[@raghavagrawal6263]

What is the mistake in below code. It is running fine and output is also coming then also its giving wrong answer. Please correct me. public static void printEncodings(String str, String ans) { if(str.equals("")) { System.out.println(ans); return; } char c = str.charAt(0); if(c != '0') { int n = c - '0'; String rem_str = str.substring(1); char ch = (char)(96+n); printEncodings(rem_str, ans+ch); } if(str.length() >= 2) { String s = str.substring(0, 2); int m = Integer.parseInt(s); if(m >= 10 && m

[@FirstLearningthanEarning]

Good morning Sir... I want to join Placement Bootcamp Course... I am 4th year Student.... Huge fan of yours.... Admiring u everytime just can be 1% of you i wish...

[@Pepcoding]

All the best. Placement Program October mei shuru hoga.

[@himanshuchhikara4918]

video is very hepful sir thankyou

[@Pepcoding]

Most welcome

[@mahakjain3732]

Can we do the same question with Recursion with ArrayList?

[@mickyman753]

itne tough question ko kitna easy bna diya sir ne

[@Pepcoding]

Thank you so much and If you like our efforts, please upvote the comments written by the students about Pepcoding here (www.quora.com/What-are-the-good-websites-to-learn-data-structures-and-algorithms )

[@SCRIPTSAG]

Thoda bahut soch paya tha sir kuch aisha logic 1 hour diye the sir

[@Pepcoding]

bdiiaa haii yrr!! keep practicing

[@SCRIPTSAG]

Esme hmesa one charcter nikalte hai ya fir pahle 2 lekin hme pahle 2 me bhi ho sakta hai koi 27 ho to uske liye bhi usko int me convert kerke check kiya fir use ch me convert kiya aur call kiya hai

[@RinkuYadav-pn4jo]

sir here is a simpler (i think) or may be cleaner implementation of the solution (in python i code): encodings = ["0", 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z'] def printEnc(nu, ans): if len(nu) == 0: print(ans) return if int(nu[0]) == 0: return if len(nu) >= 1: printEnc(nu[1:], ans + encodings[int(nu[0])]) if int(nu[:2]) = 2: printEnc(nu[2:], ans + encodings[int(nu[:2])])

[@SubodhKumar-vf4si]

is this solution right fot a test case lets say 145 ? here we can take 1,4,5 individuallly but if we take 1 separately and 45 separately it will not work !

[@DeepakGupta-zz1vf]

bhaiya yaha agar first char 0 hai toh aage jaane ki jarurat hi nahi na uske dono possibilities cancel hi hojaegi, toh kya hum ek base condition rak de kya ki if(ques.charAt('0') == '0') then return???

[@Pepcoding]

Beta, I regret to inform you that, I won't be able to answer/solve the personal doubts of each and every student over here. For clearing your doubts, you can join our community on telegram - t.me/pepcoding.

[@anjneykumarsingh4461]

Sir length 1 p bhi call lgni chaiye n Or else length 0 wale ko eliminate kr skte h

[@SCRIPTSAG]

Yes bro

[@ishanraja8162]

Wahi mai bhi nhi samjha length 1 pe call lagegi roq ki tab he toh return hoga. Unhone direct print kar diya

[@tushargupta3236]

Blank testcases tab pass ho jaenge jab aap new line print kar denge too if(ques.length == 0){ cout

[@aaquibshahzada9761]

sir chv12 should be greater then 10

[@sudhindrashenoy7992]

Hello Sir...Please tell when should we add a return statement in recursion. I am really confused about it.

[@Pepcoding]

Beta, I regret to inform you that, I won't be able to answer/solve the personal doubts of each and every student over here. For clearing your doubts, you can join our community on telegram - t.me/pepcoding.

[@sudhindrashenoy7992]

@@Pepcoding sure Sir. Thank you.

[@mickyman753]

hamne aage uske call hi nhi lagai koi in that else if block ,toh waise hi function uthar end ho gya ,but yes wha return lagana chahiye

[@stellagabriella9085]

I have searched all your videos, please tell the link where you have explained how to draw the tree required in this video Eagerly waiting

[@Pepcoding]

It is by name print zig zag

[@yashwantkumar9929]

Sir, agar a = 1, b = 2, c = 3, Na hoker Special keywords hote to Kaise approach karte Like a = _*_ b = __ c = *__* ... z = **_ Esme condition nhi lagenge n zero ke liye 1 ke ya usse jada ke lie

[@simransaigal5896]

Sir I have done the encoding as asf+char(str.charAt(0)-‘1’+’a’) But it is throwing an exception saying wrong expression. Please help.

[@komaldeepsingh6356]

you are adding 'char' to 'string' ..... so it is throwing u an error

[@arshadmanxoori07]

sir if ch12 == 0 ho jaaata hai to kya?? uske liye to likha hi nhi still code fine hai..how?

[@monu_7712]

Same doubt we have to modify that

[@octagonalcoder8048]

what will be the time complexity??

[@Pepcoding]

Beta, I regret to inform you that, I won't be able to answer/solve the personal doubts of each and every student over here. For clearing your doubts, you can join our community on telegram - t.me/pepcoding.

[@octagonalcoder8048]

@@Pepcoding ohky sure

[@utkarshagarwal587]

O(length of string)

[@priyanshgoyal9417]

this is giving time limit reached error for very large input such as "1111111111111111111111" . any idea on how to optimize it.

[@saarthakaggarwal7018]

Use simple 1-D dp

[@037_sayedramishali7]

Sir c++ mai maine Stoi fxn use kara string to int ke liye but vo kaam nhi karrha sir

[@Pepcoding]

Stoi ke liee nhi to function bnaa lijieee apnaa

[@sommayghosh4617]

stoi len 2 k liye chal jayega , single length actually character hota h toh stoi kaam ni krega, usse khud se krna pdega str[i]-'0' use krke

[@eminemrokzz8182]

A littile bit shorted version of this code public static void printEncodings(String str, String asf) { if (str.length() == 0) { System.out.println(asf); return; } if(str.charAt(0) == '0') return; // First choice i.e length number for (int i = 0; i < str.length(); i++) { String sub = str.substring(0, i + 1); int no = Integer.parseInt(sub); if (no > 26) { return; } String remstr = str.substring(i + 1, str.length()); printEncodings(remstr, asf + (char)(no - 1 + 'a')); } }

[@mihirshinde4268]

public static void main(String[] args) throws Exception { Scanner scn = new Scanner(System.in); String ques = scn.next(); printEncodings(ques, ""); } public static void printEncodings(String ques, String ans) { if (ques.length() == 0) { System.out.println(ans); return; } // 1st option // first 1 digit from 123 [1] char ch = ques.charAt(0); String roq1 = ques.substring(1); if (ch == '0') { return; } else { int chv = ch - '0'; char letter = (char) ('a' + chv - 1); printEncodings(roq1, ans + letter); } // 2nd option - first 2 digits from 123 [12] if (ques.length() >= 2) { String ch2 = ques.substring(0, 2); String roq2 = ques.substring(2); if (ch2.charAt(0) == '0') { return; } else { int chv = Integer.parseInt(ch2); if (chv

[@tanmaya2421]

public static void printEncodings(String s, String ans) { if(s.startsWith("0")){ return; } if(s.length() == 0){ System.out.println(ans); return; } char ch = (char)(s.charAt(0) +'0'); printEncodings(s.substring(1), ans + ch); if(s.length() > 1 && Integer.parseInt(s.substring(0,2))

[@wtf_nikhil]

bhot complicated ho gya sir yeh wala

[@Story.Blocks]

@pepcoding Sir online editor me language select ni ho ra..

[@Pepcoding]

Beta dubara try kr k dekho.

[@12345689atul]

hi sir , for long string its giving TLE , can u please guide me for longer strings also for example with string "111111111111111111111111111111111111111111111" this is not working on local machine

[@nishantkumarsingh6421]

hey we are only using int it is very large

[@utkarshagarwal587]

use BigInteger in Java or long long int in cpp

[@ajitmishra7689]

just memoize by creating hashmap and add ans to that map and check if it is already there for every recursion call it will reduce the complexity.

[@shivampundir1829]

ye do dislikes coding ninjas aur coding blocks walo ke hai...

[@Pepcoding]

Haha Keep learning. Keep supporting.

[@anjneykumarsingh4461]

Sorry sir smjh gye. copy pen bhut jaruri

[@Pepcoding]

cool

[@SCRIPTSAG]

Ha bhai copy pen pe tree bna ke serial wise dry run kerne ke bad samgh ata hai ki memory me kya ho rha hai chel kaise rha hai code ye sab mja ata hai dry run me sochne ke time

[@AnjaliSingh-uq9fy]

@@SCRIPTSAG ek doubt h suppose str = 231 h toh voh case kb chlega jb hum 2(single) aur 31(pair) bnaege? code me toh 1st 2 no ka hi pair bn rha h for eg 23 and 1?

[@sakshigupta8141]

@@AnjaliSingh-uq9fy nhi, code mein starting 2 numbers ka bna rha jaisr ki 2 and 23 ka

[@AnjaliSingh-uq9fy]

@@sakshigupta8141 toh hamesha first 2 no ka hi pair bnega?

[@maitohpughu5714]

********JAVASCRIPT CODE********* (OPEN FOR SUGGESTIONS) function printEncodings(num, res) { if (num.length === 0) { console.log(res); return; } else if (num.length === 1) { if (num[0] === "0") { return; } console.log(res + codes[+num[0]]); } else { let firstChar = +num[0]; let restChar = num.slice(1); if (firstChar === 0) { return; } else { printEncodings(restChar, res + codes[firstChar]); } let firstTwo = +num.slice(0, 2); let rest = num.slice(2); if (firstTwo