ZigZag Conversion - Leetcode 6 - Python

0:00 - Read the problem
1:50 - Drawing Explanation
8:30 - Coding Explanation

leetcode 6

#coding #interview #python
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[atifhu]

liked this video, disliked the leetcode problem

[henryCcc]

Using += on strings creates new strings on each iteration in linear time and space. Might I suggest using a list and appending each character (constant amortised time/space), then converting to string before returning.

[samlee]

While less elegant, I feel like the solution to this problem where you assign a list for each row and move up and down while assigning each letter from the input to a given list is a bit more intuitive. It's less space efficient but I think it's good to learn as well

[smartsoothing]

How can we come up with this type of solution in 45 min interview? 🤕

[canxingbu]

Hi, I think if you move "increment = 2 * (numRows -1)" out of for loop may be better to understand. Still a really great solution! Thank you!

[KeshavKumar]

Dang, what timing, I was searching for your solution of this question today and couldn't find it. This question is little confusing to understand. Thanks for uploading!

[pvrohanraj]

I Think this solution is really what comes to my head over the strings one, i couldn't break it down somehow. Thank you for the explanation

[Tony-ynrr]

If I had to answer this I would fail, just properly parsing the instructions felt difficult till I saw you draw the zig zag.

[eltonlobo]

Hi, Can you do Subsets 2? Couldn't find any good video for that problem. You explain every problem's solution nicely.

[butoyighyslain]

thanks Neetcode! I cant think of a use case when this would be needed in real life

[jktruimp]

Thanks for your tutorial, I can't understand this question's solutions wrote by others until I watched this video.😂

[name_surname_]

it's pretty funny though that instead of a straightforward simulation you wrote the formula that you know. good luck to come up with this formula in an interview

[ratikdubey]

In the Medium Playlist, 75-88 are the same as 89-102, I think you've added them twice by mistake. 
Thanks for coming in clutch with all your videos man, really do appreciate it.

[vipulchaudhary_js]

class Solution {
public:
string convert(string s, int numRows) {
if (numRows == 1) return s;

string ans = "";
for (int r = 0; r < numRows; r++) {
int inc = 2 * (numRows-1);
for (int i = r; i < s.length(); i += inc) {
ans += s[i];
if (r > 0 && r < numRows-1 && i + inc - 2 * r < s.length()) {
ans += s[i + inc - 2*r];
}
}
}
return ans;
}
};

[asdasddas]

Hey I just did this one. I bet your solution is 300x more elegant though

Edit: It is. :p

[licokr]

Awesome... I think I got a little bit of tricked by the section 'pointer'. I made two vairables and switch the flag in every step and increase it by the first variable or the second variable depending on the flag. But this solution is much eaiser to read and simple... Thanks for uploading this video!

[cmpe]

Hey! Your videos are great! Can you please solve leetcode problem 68 text justification ? It is a hard problem and has a 89.13% frequency of being asked.

[nathaniepeter]

I saw this question and laughed at the discussion 😂

[VINAYKUMAR-obco]

Hey can you do all top 100 questions of leetcode 🙂🙂

[nikhilshetty]

Hey, i had a bit of confusion still can you help me out
in explanation for 2nd and 3rd row you used formula as increment-2*rownumber, but in code you used + i I didn't catch that from where that "i" come from, so can you explain bit about it.