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# Average of remaining elements after removing K largest and K smallest elements from array

• Difficulty Level : Basic
• Last Updated : 08 Apr, 2021

Given an array of N integers. The task is to find the average of the numbers after removing k largest elements and k smallest element from the array i.e. calculate the average value of the remaining N – 2K elements.

Examples:

```Input: arr = [1, 2, 4, 4, 5, 6], K = 2
Output: 4
Remove 2 smallest elements i.e. 1 and 2
Remove 2 largest elements i.e. 5 and 6
Remaining elements are 4, 4. So average of 4, 4 is 4.

Input: arr = [1, 2, 3], K = 3
Output: 0```

Approach:

• If no. of elements to be removed is greater than no. of elements present in the array, then ans = 0.
• Else, Sort all the elements of the array. Then, calculate average of elements from Kth index to n-k-1th index.

Below is the implementation of the above approach:

## C++

 `// C++ implementation of the above approach``#include ``using` `namespace` `std;` `// Function to find average``double` `average(``int` `arr[], ``int` `n, ``int` `k)``{``    ``double` `total = 0;` `    ``// base case if 2*k>=n``    ``// means all element get removed``    ``if` `(2 * k >= n)``        ``return` `0;` `    ``// first sort all elements``    ``sort(arr, arr + n);``    ``int` `start = k, end = n - k - 1;` `    ``// sum of req number``    ``for` `(``int` `i = start; i <= end; i++)``        ``total += arr[i];` `    ``// find average``    ``return` `(total / (n - 2 * k));``}` `// Driver code``int` `main()``{``    ``int` `arr[] = { 1, 2, 4, 4, 5, 6 };``    ``int` `n = ``sizeof``(arr) / ``sizeof``(arr);``    ``int` `k = 2;` `    ``cout << average(arr, n, k) << endl;` `    ``return` `0;``}`

## Java

 `// Java implementation of the above approach` `import` `java.io.*;``import` `java.util.*;``class` `GFG {` `// Function to find average``static` `double` `average(``int` `arr[], ``int` `n, ``int` `k)``{``    ``double` `total = ``0``;` `    ``// base case if 2*k>=n``    ``// means all element get removed``    ``if` `(``2` `* k >= n)``        ``return` `0``;` `    ``// first sort all elements``    ``Arrays.sort(arr);``    ``int` `start = k, end = n - k - ``1``;` `    ``// sum of req number``    ``for` `(``int` `i = start; i <= end; i++)``        ``total += arr[i];` `    ``// find average``    ``return` `(total / (n - ``2` `* k));``}` `// Driver code`  `    ``public` `static` `void` `main (String[] args) {``            ``int` `arr[] = { ``1``, ``2``, ``4``, ``4``, ``5``, ``6` `};``    ``int` `n = arr.length;``    ``int` `k = ``2``;` `    ``System.out.println( average(arr, n, k));``    ` `}``}``// This code is contributed by anuj_67..`

## Python3

 `# Python3 implementation of the``# above approach` `# Function to find average``def` `average(arr, n, k) :``    ``total ``=` `0` `    ``# base case if 2*k>=n``    ``# means all element get removed``    ``if` `(``2` `*` `k >``=` `n) :``        ``return` `0` `    ``# first sort all elements``    ``arr.sort()``    ` `    ``start , end ``=` `k , n ``-` `k ``-` `1` `    ``# sum of req number``    ``for` `i ``in` `range``(start, end ``+` `1``) :``        ``total ``+``=` `arr[i]` `    ``# find average``    ``return` `(total ``/` `(n ``-` `2` `*` `k))` `# Driver code``if` `__name__ ``=``=` `"__main__"` `:` `    ``arr ``=` `[ ``1``, ``2``, ``4``, ``4``, ``5``, ``6` `]``    ``n ``=` `len``(arr)``    ``k ``=` `2` `    ``print``(average(arr, n, k))` `# This code is contributed by Ryuga`

## C#

 `// C# implementation of the above approach` `using` `System;``public` `class` `GFG {`` ` `    ``// Function to find average``    ``static` `double` `average(``int` `[]arr, ``int` `n, ``int` `k)``    ``{``        ``double` `total = 0;` `        ``// base case if 2*k>=n``        ``// means all element get removed``        ``if` `(2 * k >= n)``            ``return` `0;` `        ``// first sort all elements``        ``Array.Sort(arr);``        ``int` `start = k, end = n - k - 1;` `        ``// sum of req number``        ``for` `(``int` `i = start; i <= end; i++)``            ``total += arr[i];` `        ``// find average``        ``return` `(total / (n - 2 * k));``    ``}` `    ``// Driver code`  `        ``public` `static` `void` `Main() {``                ``int` `[]arr = { 1, 2, 4, 4, 5, 6 };``        ``int` `n = arr.Length;``        ``int` `k = 2;` `        ``Console.WriteLine( average(arr, n, k));` `    ``}``}``//This code is contributed by 29AjayKumar`

## PHP

 `=n``    ``// means all element get removed``    ``if` `(2 * ``\$k` `>= ``\$n``)``        ``return` `0;` `    ``// first sort all elements``    ``sort(``\$arr``) ;``    ` `    ``\$start` `= ``\$k` `;``    ``\$end` `= ``\$n` `- ``\$k` `- 1;` `    ``// sum of req number``    ``for` `(``\$i` `= ``\$start``; ``\$i` `<= ``\$end``; ``\$i``++)``        ``\$total` `+= ``\$arr``[``\$i``];` `    ``// find average``    ``return` `(``\$total` `/ (``\$n` `- 2 * ``\$k``));``}` `// Driver code``\$arr` `= ``array``(1, 2, 4, 4, 5, 6);``\$n` `= sizeof(``\$arr``);``\$k` `= 2;` `echo` `average(``\$arr``, ``\$n``, ``\$k``);` `// This code is contributed by Ryuga``?>`

## Javascript

 ``
Output:
`4`

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