BS-26. Find Peak Element-II | Binary Search

Problem Link: bit.ly/3Ckb4Rb
Please watch part-1: • BS-9. Find Peak Element
Notes/C++/Java/Python codes:
We have solved the problem, and we have gone from brute force and ended with the most optimal solution. Every approach's code has been written in the video itself. Also, we have covered the algorithm with intuition.
Full Course: bit.ly/tufA2ZYt
You can follow me across social media, all my handles are below:
Linkedin/Instagram/Telegram: linktr.ee/takeUforward
0:00 Introduction of Course

[@iammysterious-ud9cf]

Striver..... PLEASE CONTINUE A TO Z DSA Course....From Step 5(strings) , it is incomplete(no videos for the questions)... Your videos are very useful in intuition building and finding approach... PLEASE DONT LEAVE US IN THE MIDDLE😢😢😢...I hope you respond to the requests for the guys like me..

[@bhubeshsr6281]

solve by yourself - thats his intuition

[@sachinchoudhary4142]

Yes please🙏🙏

[@Dipanshutripathi2407]

Yes Please

[@krishnayadav5601]

yes please sir

[@sachitkumbhat2004]

We love you Striverr!!!

[@kathakalisaha9735]

Those who watches your videos completely will never say you use cpp , they are the ones who dont watch the intuition part, directly jump into the code

[@saibingi6980]

I request you to please make videos in Bit Manipulation, Heaps, Strings, and Disjoint-set in the upcoming sessions.

[@godson200]

He already has about 10 videos on disjoint set in the graph series. Maybe that can help.

[@rekhabisht6709]

Phle itna khatm krle

[@dumpster-jackson]

@@rekhabisht6709 Ab??

[@zerobear-xf7qh]

nice solution i dont think i would come up with this solution on my own

[@sundaramkumarsingh8448]

clear cut explanation. Thank you Striver

[@securelyinsaycure]

Striver you are a godsend to so many of us! Thank you 🙏

[@cenacr007]

Array and Strings are the most important for interviews, please make a playlist on strings.

[@LearnwithEase20]

please make videos on string and other topic it is much needed no one explains like you!🙂

[@stith_pragya]

Thank You Much for this wonderful video..........🙏🏻🙏🏻🙏🏻🙏🏻🙏🏻🙏🏻

[@jeehub041]

What an approach mind blown 🙌🙌

[@anonymous-ms2en]

love you striver ,clear explaination

[@ayushagarwal5271]

This man is a genius!

[@GeetainSaar]

your skin glowing in whole video

[@NazeerBashaShaik]

Understood, thank you.

[@amanpatel6203]

long awaited

[@viveksoni3269]

Very Nice!!!!

[@utkarshtrivedi9866]

Understood, even just looking at pseudo code, I was able to code it myself.

[@user-or5oz1pk2x]

Thanks a lot Bhaiya

[@AshishSingh-he2qo]

Understood 🎉🎉

[@JothiprakashThangaraj]

sudo code is sufficient for any developer to write code in any language , understood thanks a lot !!

[@binarybardic4667]

Thanks a lot......!

[@vikassinghbisht7305]

striver you are just too good

[@rahulgoel7652]

I am unsure if first method would have O(mn *4) TC. You are traversing the matrix once, i.e. O(mn). For each element, checking the neighbors is constant time, so it wont be 4 times the number of elements

[@hashcodez757]

Understood!!

[@vishious14]

Understoood !!!!!

[@ddevarapaga5134]

Understood brother

[@tanvirkekan6111]

This is an interesting soln: x,y = 0, len(mat[0]) - 1 while x < len(mat) or y >= 0: if x + 1 < len(mat) and mat[x + 1][y] > mat[x][y]: x += 1 elif y - 1 >= 0 and mat[x][y - 1] > mat[x][y]: y -= 1 else: break return [x, y]

[@shivamdubey3798]

Bhaiya please video continue to upload Kara Karo mera ye week topic haa🙏🙏

[@anand_yv]

Understood

[@iammysterious-ud9cf]

Please Start Linked Lists

[@soumiyamuthuraj3516]

awesome

[@surbhirathore._]

Done!!!

[@nayankhuman1043]

Understood :)

[@sidharthsharma341]

What are the upcoming topics?after this

[@viratlover6206]

understood

[@chandandasari6351]

bro plzz make a videos on string problems it was missed in play list bro strivers a to Z sheet plzz upload videos

[@anusmitahait2329]

Problem seemed so intimidating at the begining, later on was simple variation of peak.

[@VishalKumar-uk5uc]

Ek month wait Kiya ek video ke liye

[@AbdulRehman-ee8zc]

sir khan thay aap aap hi k lecture ka intizar tha

[@MJBZG]

didn't really understand but will try more

[@Harshitbejsbsksjnw]

Just a little doubt, when you say we can find the maximum element in the matrix and it will surely be the peak as well. What about the fact that there can be two maximums in the matrix and both lie adjacent to each other? And the question says that the element should be strictly greater than its adjacents......

[@TheAI-Tutor]

But instead of traversing vertically, can't we just Traverse horizontally and find the maximum element to do STL and then check for the upper and lower element? and discard the upper half/lower half then?

[@shaiksoofi3741]

tq

[@vijeshsshetty]

linked list series plss

[@codeman3828]

Undertsood

[@adilkevin6220]

ARTICLE column is empty for this problem. Please attach it.

[@gugulothsrilakshmi8729]

written article not there in description

[@swagcoder]

For this problem, in leetcode , it’ll fail one test case where there are multiple peaks in the same row, that one is different scenario though, in this problem it is assumed that there will be only one peak per row , because you can’t eliminate directly in case of multiple peaks.

[@takeUforward]

this works for it also, because even if it has multiple peaks, it will find ,watch the first video to understand why it works

[@swagcoder]

Thanks for replying Stiver, Understood

[@guttulavybhav1030]

striver please upload videos on strings it is difficult to go to others videos....

[@nishantsatere9350]

understoddddddddd

[@RitikaMajumdar__F]

bhaiya the java cpp notes's link is not given in the description. Please do share it.

[@SurajYadav-bt9jb]

I have one doubt regarding BS that it can apply on sorted ones, but here 2D Matrix is not sorted so how can we apply BS on it , please resolve my confusion

[@learn_in_shorts]

Bhaiya mey aapka binary tree ka playlist se tree padh rha hu but jab aap iss video mey jaise padhete hai to sab samjh aata hai but tree wala mey aisa kuch samjh nahi aa rha hai jab jab aap board pr padhye jab tak to sab samjh aaya but uske baad kuch jyada nahi aaya 😊 plz bhaiya aap iss video ki format mey videos banaya kariye plz and do something trees also

[@shivamkumar-hz7jt]

strings ke video upload krdo pls

[@prikshit_sharma4071]

Bhaiya linkedlist start krdo iske badh

[@saketjaiswal9381]

linked list striver bhaiya

[@GeetainSaar]

give its article also

[@mithileshkumbhar7968]

Striver......The link to this problem on your page is not opening to view the code and intuition.

[@AkashBisht-cq3ys]

1st july mon 9.13

[@mohitsinghnitjsr2652]

how many videos more to come

[@charuprabha9696]

🙇‍♀🙇‍♀🙇‍♀🙇‍♀🙇‍♀🙇‍♀

[@crazybro4383]

8:00

[@rahulhembram4519]

UnderStood

[@infinity2creation551]

You are calling col ko row ...

[@dhakadkumman4239]

100th comment of video

[@mahimagautam1810]

class Solution { public int findMaxIndex(int[][] mat,int mid,int n) { int maxi = -1; int ind = -1; for (int i = 0; i < n; i++) { if (mat[i][mid] > maxi) { maxi = mat[i][mid]; ind = i; } } return ind; } public int[] findPeakGrid(int[][] mat) { int ans[] = {-1,-1}; int n = mat.length; int m = mat[0].length; int low =0; int high = m-1; while(low=0 ? mat[index][mid-1]:-1; int right = mid+1left && mat[index][mid]>right){ return new int[]{index, mid}; } else if (mat[index][mid]

[@harshit.53]

i don't understand why people complain about only using cpp...first of all he discusses the idea behind the code and then writes a simple pseudo code...secondly, even if he uses cpp, any good coder can easily convert that code into any other language, maybe in other languages the function name and syntax is different, so u just need to use the functions provided by ur language

[@daniyalhussain5231]

Solution in C++: class Solution { public: int findMaxIndex(vector&mat,int col,int rows) { int maxi=INT_MIN; int maxIndex; for(int i=0;imaxi) { maxi=mat[i][col]; maxIndex=i; } } return maxIndex; } vector findPeakGrid(vector& mat) { vectorans(2); int rows=mat.size(); int cols=mat[0].size(); int low=0,high=cols-1; while(low=0)left=mat[maxElementRowIndex][mid-1];//edge case int right=-1; if(mid+1left&&curr>right) { ans[0]=maxElementRowIndex; ans[1]=mid; return ans; } else if(curr

[@user-xr5tm4dk9v]

Jeetu bhaiya equivalent

[@cenacr007]

us

[@PrinceKumar-ef1xf]

vector findPeakGrid(vector& mat) { int startCol = 0, endCol = mat[0].size()-1; while(startCol = startCol+1 && mat[maxRow][midCol-1] > mat[maxRow][midCol]; bool rightIsBig = midCol mat[maxRow][midCol]; if(!leftIsBig && !rightIsBig) return vector{ maxRow, midCol}; else if(rightIsBig) startCol = midCol+1; else endCol = midCol-1; } return vector{-1,-1}; }

[@Lucifer0872]

Biltu kaka Zindabad

[@adityauditsingh5986]

first view xD

[@dayashankarlakhotia4943]

public class solution { public static int []find Peek Grid(int [][]grid){ int n=grid. length,m=grid [0].length; int l=0,r=m-1; while (lgrid [idx][mid +1]){ r=mid; }else { l=mid-1; } return new int []{l,find max(grid [l])}; } public static int find max(int []col){ int index =0,n=col length; for(int i=0;icol[index]) index =i; } return index; } }; 🎉❤

[@AvaneeshSrivastava-lm5vj]

understood. thank you. you should sleep a bit more.

[@RAJPATEL-ir7ly]

O(n+m) BFS class Solution { public: vector findPeakGrid(vector& mat) { int i = 0 ; int j = 0 ; int n = mat.size() ; int m = mat[0].size() ; while(true){ int flag = 0 ; vector coordinates = {{1,0} , {0,1} , {-1,0} , {0,-1}} ; int maxi= -1 ; int newRow =0 ; int newCol = 0 ; for(auto coordinate : coordinates){ int x = i+coordinate.first ; int y = j+coordinate.second ; if(x>=0 && y>=0 && x

[@sanjayp.m7008]

why cant i use the logic of matching the row and col to mid and considering this matrix as a 2d array. i tried this but only 46 testcases passed in the leetcode qn. class Solution { public: vector findPeakGrid(vector& mat) { int n = mat.size(); int m = mat[0].size(); int low = 0; int high = n * m - 1; while (low = 0) ? mat[row][col - 1] : INT_MIN; int bottom = (row + 1 < n) ? mat[row + 1][col] : INT_MIN; int top = (row - 1 >= 0) ? mat[row - 1][col] : INT_MIN; if (el > right && el > left && el > top && el > bottom) { return {row, col}; } if (right > el) { low = mid + 1; } else if (left > el) { high = mid - 1; } else if (bottom > el) { low = mid + 1; } else { high = mid - 1; } } return {-1, -1}; } };

[@ishangujarathi10]

why am i getting a runtime error when i submit the solution on leetcode? @striver??

[@ajithc5505]

int left = mid-1>=0 ? mat[index][mid-1]:-1; int right = mid+1

[@tejaswaniguttula5961]

@@ajithc5505 Hi vector findPeakGrid(vector &g){ // Write your code here. int rows = g.size(); int cols = g[0].size(); int low = 0, high = cols-1; while(low max_ele){ max_ele = g[i][mid]; index = i; } } int left = mid-1 >= 0 ? g[index][mid-1] : -1; int right = mid +1 < cols ? g[index][mid+1] : -1; if(max_ele > left && max_ele > right){ return {index, mid}; } else if(max_ele < g[index][mid-1]){ high = mid-1; } else{ low = mid+1; } } return {-1, -1}; } }; Though I applied edge cases why I am getting runtime error for this testcase?? Test case: [[10,50,40,30,20],[1,500,2,3,4]]

[@user-fu4lb7fw1t]

@@ajithc5505 thanks brother it works now

[@NazeerBashaShaik]

Understood, thank you.

[@user-tk2vg5jt3l]

Thank you Bhaiya

[@_sf_editz1870]

Understood

[@culeforever5408]

understood

[@dewanandkumar8589]

Understood

[@abhishekprasad010]

Understood

[@ashishpradhan6250]

understood

[@hardikpatel352]

understood

[@Shivi32590]

understood