ma5termind's blog

HackerRank HourRank-17
By ma5termind, history, 8 years ago, In English

Hi Codeforces,

I am taking this opportunity to announce HackerRank HourRank 17, a 60 minute contest where the fastest coder wins!. The contest will be held on 16:00 UTC Thursday, 2nd February, 2017. You can sign up for the contest here. Contestants will be given 4 problems and 1 hour to solve. I recommend all of you to read all the problems as each problem contains some interesting subtasks. Top 10 global winners will get cool HackerRank T-shirts. Note that contest will be rated for all users.

By this time you can probably guess, i am author of this contest and i promise you all to deliver an interesting problem set with something for all. I really want to thank danilka.pro for testing all the problems and helping me to come up with nice problem set. My special thanks to Shafaet for giving me another opportunity and motivate me to work hard for this contest. Also, thanks to svanidz1 for presolving the contest and providing his valuable feedback.

Scoring will be posted right before the contest and editorials will be published right after the contest.

Hope to see you participating.

Good Luck & Have Fun.

UPDATE 1: Score Distribution 15, 30, 60, 80.

UPDATE 2: Contest will be started in less than 15 minutes.

UPDATE 3: Drum roll please and top 10 winners are:

  1. RomaWhite
  2. xllend3
  3. uwi
  4. jonathanirvings
  5. abcdef6199
  6. [user:vm450]
  7. satyaki3794
  8. zscoder
  9. rajat1603
  10. [user:hoigamn_xing]

Please feel free to comment your codeforces handle. I will update the post. Any more comments and feedbacks are welcome.

  • Vote: I like it
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  • Vote: I do not like it

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8 years ago, # |
  Vote: I like it 0 Vote: I do not like it

Was brute force similar to this one supposed to pass in problem C? (I just used that fact that there are atmost 128 divisors of any number less than 100000. But still complexity-wise I thought it might TLE on some cases)

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    8 years ago, # ^ |
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    Can you elaborate your approach

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      8 years ago, # ^ |
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      I just simply check if "x" can be some possible answer or not. First of all it should be a divisor of any of the numbers , a[i], where u <= i <= w. Then I simply iterate over all multiple of u in array "b", lying from v to z. If any such pair is found, i update the answer and mark the element "x" and never do the same process on it again.

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8 years ago, # |
← Rev. 2   Vote: I like it +8 Vote: I do not like it

Test cases for problem 4 were a bit weak, I think. I got 71/80 points by using bitsets of size 5e5 to represent the parity of colours along the path from 1 to every other vertex. All cases passed except one which gave segmentation fault. Don't know if that was intended or not.

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    8 years ago, # ^ |
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    Yes, you shouldn't have got this much score as your solution was not intended. Your solution takes advantage of number of distinct values and size of tree and ensuring both in a test case was difficult. Also, hackerrank does not have system where we can couple multiple test files & you will get score only when you pass them all. I will see if we can do something to avoid such scenarios. I feel relaxed atleast that one file did not let you get full score.

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8 years ago, # |
  Vote: I like it 0 Vote: I do not like it

rajat1603 is rajatde160398

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