Given an array arr containing N Positive integers, and two integers K and M, The task is to calculate the maximum amount of M Subsets of size K.
Example:
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input: arr[] = 1, 2, 1, 2, 6, 7, 5, 1, M = 3, K = 2
Productivity: 33
explanation: The three subsets selected are [2, 6], [6, 7] and [7, 5] Respectively. So, sum: 8 +12 +13 = 33input: arr[] = 1, 4, 1, 0, 6, 7, 5, 9, M = 4 ,, K = 5
Productivity: seventy six
access: The problem can be solved by pre-calculating the prefix amount up to each index I am Who will tell us the sub-amount from 0 To I am. You can now use this prefix sum to find the sum of each K-size subset, using the formula:
Sub-array sum from i to j = prefix sum to j – sum prefix up to i
After finding the sum of all the subsets, select the maximum M Sub-amounts for calculating the answer.
To resolve this issue, follow these steps:
- Create a vector prefixSum Where each node represents the sum of the prefixes up to this index, plus another vector subarraySum, To store all subsets the sum of the size K.
- Now, run a loop from i = K To i = N And calculate the sum of each subset using the formula subarraySum[i-K, i]=prefixSum[i]-prefixSum[i-K] And push him Doctor subarraySum.
- Type subarraySum In descending order and add the top M Elements to get the answer.
- Print the answer according to the observation above.
The following is the application of the above approach:
C ++
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Time complexity: On)
Auxiliary space: On)
