Climbing The Leaderboard HackerRank Solution 

JAVAAID community: RU-vid recently changed the way they monetize my content. My channel now needs 1,000 subscribers so it would be awesome if you could show your support by both watching my videos and subscribing to my channel if you haven’t already done so. Monetizing my videos allows me to invest back into the channel with new equipment so a small gesture from you goes a huge way for me. Many thanks for your support!

Finally earned 20 points after submitting this solution. That's the power of Binary search. Thank you !!

I was finally able to pass all the test cases in C++. Here is my implementation of the binary search method and the method we had to fill on hackerrank int binary_search(vector &ranked, int key, vector &rank){ if(key>ranked[0]) return 1; else if(key

Great explanation, thanks! For posterity (using Java SE 8), I had a timeout failure on test case 7 even when doing binary search. I had put the binary search in it's own method for readability, and I passed it the score to be tested, the ranking array, and the scores array as parameters (so I only made the ranking array once, and then just passed it as a parameter). When I pulled the binary search into the solution method, it ran within the timing parameter. I guess I was riding right on the edge, and taking out the extra method calls (which I don't believe added a whole lot of complexity at run time) got me in the window.

I use C++, while using vectors test case 6 and 7 were timed out so try giving a chance to array and worked fine, I don't know the reason behind it but my code worked. Thank man!!

The first condition should check for >= instead of > otherwise testcase 5 fails: scores=[1], alice=[1,1]. if (aliceScore >= scores[0]) res[i] = 1; But this is a great explanation. Thank you.

Thank you for the solution sir!! My solution was very close to this, the only thing I couldn't figure out how to modify the Binary Search algorithm.

sir, test case 6 is failed(TLE) in c++. I followed exactly the same approach as you have taught.

I don't even know how to it with the basic approach lol

Thanks for your detailed explanation. It really helps! I clicked 'Subscribe' Button haha

Thank you very much! Your idea to make an array RANK realy helped! And binary search of cause.

implemented the same solution in c and got two test case failures. here is the code for reference: int binarysearch(int n,vector arr) { int lo=0,hi=arr.size()-1,mid; while(lon) lo=mid+1; else if(arr[mid]

Great Video.Helpled me a lot to progress further

hello sir ,nice explanation , in this explanation if 120 number got first rank then automatically 100 will get 2nd and 50 get 3rank is it rt? ..but in your example the ranks are not changing?..please explain.

Can we just use a treemap to store the ranks initially and then instead of us doing the binary search, we can just take floorKey and ceilingKey and calculate accordingly.

great tutorial. but can you add subtitle for the video? Thank you

If done in python, the entire search operation can be handled by the bisect method in the bisect library

Great video...!!!

Thanks a lot sir. I was thinking of exactly same solution but was messing up things in binary search.

Great explanation

Thanks for great video. I do have a question. After 120 is inserted, aren't we supposed to update the rest ranks since 120 is now #1, 100 #2, and so on?

The Kanhaiya we need...

superb...!

i don't understand why in the second else if you have used ">=" and why not just ">. Please reply

How can we do this using ArrayList instead? They have changed the parameters.

didn't understood the 2nd else if statement in binary search... if key is smaller than mid than how it can be greater than or equal to mid+1 element

Cool video

it takes o(n) space

Good explanation

but this program give the wrong ans in case score{100,70,50,45,23} or Alice { 55,100,110,120} for all 100 or 110 and a120 gives the same result 1 1 1 ?

hello, I used the exact implementation except changing the scores array to list (Since that's the method parameter type) however 8 tests failed: Here's the code I've done, basically just the array to list conversion : private static int binarySearch(List ranked, int key) { int lo = 0; int hi = ranked.size() - 1; while (lo key && key >= ranked.get(mid+1)) { return mid + 1; } else if (ranked.get(mid) < key) { hi = mid - 1; } else if (ranked.get(mid) > key) { lo = mid + 1; } } return -1; } public static List climbingLeaderboard(List ranked, List player) { // Write your code here int[] alice = player.stream().mapToInt(i->i).toArray(); int n = ranked.size(); int m = alice.length; int res[] = new int[m]; int[] rank = new int[n]; rank[0] = 1; for (int i = 1; i < n; i++) { if (ranked.get(i) == ranked.get(i-1)) { rank[i] = rank[i - 1]; } else { rank[i] = rank[i - 1] + 1; } } for (int i = 0; i < m; i++) { int aliceScore = alice[i]; if (aliceScore > ranked.get(0) ) { res[i] = 1; } else if (aliceScore < ranked.get(n-1) ) { res[i] = rank[n - 1] + 1; } else { int index = binarySearch(ranked, aliceScore); res[i] = rank[index]; } } return Arrays.stream(res).boxed().collect(Collectors.toList()); } I'm in desperate trying to debug, the 2 sample cases passed with no problem tho, I'd be really appreciate if you could try my code on HackerRank and see if you could find out the bug, Thank you!

i tried this method and it passes all the test cases vector climbingLeaderboard(vector ranked, vector player) { vector ranks; // here storing the player rank vector uranked; //here getting only unique values int i,j; for( i=0;i=0 && j

Thanks for posting your solution; however, I still don't understand what the subtask actually means. Does it mean that 60% of all cases are between 0 and 200 players (n) or Alice games (m)?

which software is used to draw the content and explain ?

scores=[100,90,90,80] alice=[85,95,97] code is not for this test case i guess rank should be 4,3,2 it is giving output as 3,2,2

Cool 👍🏽

Can you please do FlatLand SpaceStation? I’m very confused on that one...

how did it occur to u that u should perform binary search? nice explanation tho kudos :)

Does anyone know what should be the optimization for C++, in order to get the 6th test case passed ?

your rank array will be wrong if the scores array has more than 2 of the same scores eg {100,100,100,90,90,90} in this case your rank array will be {1,1,1,2,2,2} but it should be {1,1,2,3,3,4}

thank you so much

I implemented your code using c++ but there was one test case that showed "timed out" it was test case 6

thanks so much for this. you made this exercise really simple. thanks again, sir.

I also scored the 20 marks..😀

TLE hai sir ji apke code me

can anyone explain will this logic will work if in alice array their are more then one number greater then score[0] value will all number greater then score[0] will get first rank because no where we are updating scores array

public static List climbingLeaderboard(List ranked, List player) { int m=ranked.size(); int n=player.size(); int rank[]=new int[m]; List res=new ArrayList(); rank[0]=1; for(int i=1;ialiceScore && aliceScore>=ranked.get(mid+1)) { return mid+1; } else if(aliceScore>ranked.get(mid)) { high=mid-1; } else if(aliceScore

this is my code Listresult=new ArrayList(player.size()); ListRank=new ArrayList(); int hi=ranked.size()-1; Rank.add(0,1); for(int i=1;i= ranked.get(hi)) hi -= 1; if (hi == -1) result.add(i,1); else result.add(i,Rank.get(hi)+1); } return result; }

It gives a timeout error in cpp for testcase 6 and 7

Please Provide the Climbing the Leaderboard Solution using List method class Result { /* * Complete the 'climbingLeaderboard' function below. * * The function is expected to return an INTEGER_ARRAY. * The function accepts following parameters: * 1. INTEGER_ARRAY ranked * 2. INTEGER_ARRAY player */ public static List climbingLeaderboard(List ranked, List player) { // Write your code here ranking =[] leaderboard = sorted(set(scores)t, reverse = True) l = len(leaderboard) for a in alice: while (l > 0) and (a >= leaderboard[l-1]): l -= 1 rankings.append(l + 1) return rankings } public class Solution { public static void main(String[] args) throws IOException { BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in)); BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(System.getenv("OUTPUT_PATH"))); int rankedCount = Integer.parseInt(bufferedReader.readLine().trim()); String[] rankedTemp = bufferedReader.readLine().replaceAll("\\s+$", "").split(" "); List ranked = new ArrayList(); for (int i = 0; i < rankedCount; i++) { int rankedItem = Integer.parseInt(rankedTemp[i]); ranked.add(rankedItem); } int playerCount = Integer.parseInt(bufferedReader.readLine().trim()); String[] playerTemp = bufferedReader.readLine().replaceAll("\\s+$", "").split(" "); List player = new ArrayList(); for (int i = 0; i < playerCount; i++) { int playerItem = Integer.parseInt(playerTemp[i]); player.add(playerItem); } List result = Result.climbingLeaderboard(ranked, player); for (int i = 0; i < result.size(); i++) { bufferedWriter.write(String.valueOf(result.get(i))); if (i != result.size() - 1) { bufferedWriter.write(" "); } } bufferedWriter.newLine(); bufferedReader.close(); bufferedWriter.close(); } } Please correct the Class result code and provide the Solution. I am getting compile time Error.

Could You help I am getting time out on 3 cases: static int[] climbingLeaderboard(int[] scores, int[] slice) { int rank[] = new int[scores.length]; rank[0]=1; for(int i=1;i

optimised but still fail to pass case 6,7,9 code: int f,l; int bs(vectors,int f,int l,int x) { int as=0; while(l>=f) { int m=(f+l)/2; if(x>=s[m]) { if(x

Thank you for your help. Tip : pls don"t explain like we are 5 years old because it's getting boring to watch :)

its not working in cpp . It gives time error

New content would be appreciated

one test case still not working. you wasted my time.