4. Print this pattern using Recursion-Write optimised recursive code that will impress interviewer🤭

Let’s write some code together?

You can practice the question here-

Subscribe and hit the notification icon to get notifications and learn with me everyday!! ❤️❤️

#dsa #softwaredeveloper #interviewpreparation

[codefromscratch-keertipurswani]

We are going to practice many questions together. Keep up the energy with me ok?

[jasmindersingh]

Mam, I have watched all videos of your recursion. This problem was actually based on the previous problem, and i solved it with no flag and one recursion function only. Without any mistake. That is why because you are the best teacher of youtube...

[thenameisafsal]

what an awesome lecture, thank you for making recursion a lot easier ma'am🙏🙏

[unknowncoder]

Able to write the optimized code by myself. Thanks 😍

[skharel]

This is way better than I did by checking condition and adding flag. I have never thought it can be done with so less lines of code.
Thank you!!

[simranvolunesia]

SUMMARY


Approach 1: Using FLAG

Keep "inc" flag to keep note of increasing/decreasing scenario and push elements accordingly

void helper(vector<int> &res, int N, int present, int inc){

res.push_back(present);

if(inc){

if (present == N) return;
else helper(res, N, present+5, true);

}else{

if(present-5 > 0) helper(res, N, present-5, false);
else helper(res, N, present-5, true);

}

}

Approach 2: Without using FLAG

Go on printing while traversing down the tree and then upward

void helper(vector<int> &res, int N)
{
if (N <= 0) { res.push_back(N); return; }
res.push_back(N);
helper(res, N-5);
res.push_back(N);
}

[tjmanojofficial]

Additional condition included for this problem in practice problem.
if(N <= 0) return {N};

if the number is less than or equal to zero return that number only. Otherwise print the pattern.

[santhoshsai]

This is beautiful!! Just played with the scope of the variable. I did it by checking my arraylist for termination and for recursion but this is way simpler and actually this is how it needs to be done. Thank you di!!😁

[shaikmansoor]

Thanks, this refreshed my recursion concepts

[shashwatraghuwanshi]

I'll have to watch video was really nice.

[arunkumarmohandas]

Present. Stopped the vedio at 3:43 minute and tried myself once:

public class {

public static void main(String[] args) {
printNumbers(16);
}

private static void printNumbers(int n) {
if (n <= 0) {
System.out.println(n);
return;
}
System.out.println(n);
printNumbers(n - 5);
System.out.println(n);
}
}

[nidhikumari]

Thank you so much mam! I was able to do it after you gave the hint.😅

[galepraveen]

didi, ye cheez ekdam se dimag me nhi aati h, dekh ke bohot zyada seekhne ko mila

[nidhibansaliitr]

your hint that its same as we wrote yesterday gave the idea to write the a recursive function with just number as input. :)

[rtarts]

present mam...Can you please guide that how to install thread library PC?

[vignesh]

After recursion series, please make video about time and space complexity

[Mitansh_Agrawal]

ma'am can you also tell the same code in java?

[phalgunibumhyavarapu]

Keerthi, I have been following your videos. Thank you for this. Can you please post the corresponding leetcode link / problem link as well . Thank you!

[theepiceditz]

It's hard still not got the logic, watching frm pt.1:)