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Round-3 Ode 2 Code, 2021
By prithwiraj15, 3 years ago, In English

Ode 2 Code 2021 Round-3

Round 3 of Ode 2 Code gave only one question with a total time of 45 mins to solve it. I was not able to solve this problem. Can anyone help me ? PS :- The competition is already over, hence it the question can be disclosed now

Question Statement

You are given

  • An array A of N integers.

  • And M queries consist of three integers k, y and x.

Beauty of a array A[1], A[2], A[3], A[4],...., A[N] is defined as A[1] + A[2] + A[3] + A[4] + .... + A[N].

For each query, k, y, x, you are given the following conditions :-

  • Let U be the bitwise AND of the beauties of any y subarrays among all subarrays of size k.

  • And, Z = U | x, where | is the bitwise OR operation.

Calculate the maximum possible value of Z for all queries.

Constraints

  • 1 <= N <= 1000

  • 1 <= M <= 1000

  • 1 <= Ai <= 10^9

  • 1 <= ki <= N

  • 1 <= yi <= N-ki+1

  • 1 <= xi <= 10^9

Sample Test Cases

1) Sample Case 1

N = 5

M = 2

A = [1, 2, 3, 4, 5]

Q = [[2, 3, 9], [3, 2, 17]]

Approach

For the first query

  • We have 4 subarrays [1, 2], [2, 3], [3, 4], [4, 5] with beauties 3, 5, 7, 9 respectively.

  • You can select bitwise AND of 3 beauties, i.e 3 & 5 & 7 = 1, so U = 1.

  • Z = (1 | 9) = 9. This is the maximum possible.

For the second query

  • We have 4 subarrays [1, 2, 3], [2, 3, 4], [3, 4, 5] with beauties 6, 9, 12 respectively.

  • You can select bitwise AND of 2 beauties, i.e 9 & 12 = 8, so U = 8.

  • Z = (8 | 17) = 25. This is the maximum possible.

2) Sample Case 2

N = 5

M = 2

A = [5, 4, 2, 4, 9]

Q = [[2, 2, 7], [2, 3, 6]]

Approach

For the first query

  • We have 4 subarrays [5, 4], [4, 2], [2, 4], [4, 9] with beauties 9, 6, 6, 13 respectively.

  • You can select bitwise AND of 2 beauties, i.e 9 & 13 = 9, so U = 9.

  • Z = (9 | 7) = 15. This is the maximum possible.

For the second query

  • We have 4 subarrays [5, 4], [4, 2], [2, 4], [4, 9] with beauties 9, 6, 6, 13 respectively.

  • You can select bitwise AND of 3 beauties, i.e 6 & 6 & 13 = 4, so U = 4.

  • Z = (4 | 6) = 6. This is the maximum possible.

Please look into this problem.

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Comments Comments (15)
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3 years ago, # |
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Constraints?

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    3 years ago, # ^ |
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    Updated the post with constraints now

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      3 years ago, # ^ |
      ← Rev. 2   Vote: I like it 0 Vote: I do not like it

      This can be done in MNlog(max(A)) , just complement x, let x1 be the complement of x. First find out all sum with subarray size k. Start from the highest set bit of x1, find if there exist at least y elements with the set bit as highest set bit, if yes add that to answer and otherwise move to next bit, and check the same. Finally add all the set bits of x to the answer as well.

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3 years ago, # |
← Rev. 2   Vote: I like it +1 Vote: I do not like it

On a side note, Is there anyone who passed all testcases in round 2 but was not selected for round 3? If it was based on speed , then any idea what the cutoff time was?

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    3 years ago, # ^ |
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    Yeah i was able to pass all the test cases of my given problem in round 2, but didn't get selected for Round 3!

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    3 years ago, # ^ |
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    Yeah me.

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    3 years ago, # ^ |
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    I think about 30 mins, cuz i completed mine with about 16-17 mins left.

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    3 years ago, # ^ |
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    I see, thanks for the response!!

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    3 years ago, # ^ |
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    I had submitted under 15 mins but not selected.

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      3 years ago, # ^ |
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      Yeah , same.

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      3 years ago, # ^ |
      ← Rev. 2   Vote: I like it 0 Vote: I do not like it

      I was able to complete my test in 6 mins, but was not selected :(

      P.S. I didn't even get a rejection mail

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    3 years ago, # ^ |
      Vote: I like it +2 Vote: I do not like it

    No idea lol, I was done in like 7-8 mins. They probably thought I cheated

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3 years ago, # |
← Rev. 3   Vote: I like it 0 Vote: I do not like it

In my case,It took 35 min to understand problem. Problem statement was too bad. when I understood question ,the time remain was less so I got panic and I quit the test.but after few hour,I started doing code and I solved the question in 8 min.[problem]

(https://xp.io/storage/YogVxoL.png)

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    3 years ago, # ^ |
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    I had this same problem . Understanding the problem statement was tougher than solution..xD . It took me like 15-16 minutes to understand it and 10 minutes to solve .

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