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# Maximise count of elements that are strictly greater in a subsequence than their average

Given an array arr[] of size N containing positive integers, the task is to find the maximum number of elements that can be deleted from the array using any number of operations. In one operation, select a subsequence from the given array, take their average and delete the numbers which are strictly greater than that average from the array.

Example:

Input: arr[] = {1, 1, 3, 2, 4}
Output: 3
Explanation:
Operation 1: Choose the subsequence {1, 2, 4}, average = (1+2+4)/3 = 2. So arr=4 is deleted. arr[]={1, 1, 3, 2}
Operation 2: Choose the subsequence {1, 3, 2}, average = (1+3+2)/3 = 2. So arr=3 is deleted. arr[]={1, 1, 2}
Operation 3: Choose the subsequence {1, 1}, average = (1+1)/2 = 1. So arr=2 is deleted. arr[]={1, 1}
No further deletions can be performed.

Input: arr[] = {5, 5, 5}
Output: 0

Approach: The catch in this problem is that all elements except the minimum one can be deleted from the array because if only the minimum element is used to create the subsequence, then its average is basically the same element and all the other elements can be deleted. Now to solve this problem, follow the below steps:

1. Find the frequency of minimum element, say freq.
2. Return N-freq as the answer to this problem.

Below is the implementation of the above approach:

## C++

 `// C++ code for the above approach` `#include ``using` `namespace` `std;` `// Function to find the maximum number of``// elements that can be deleted from the array``int` `elementsDeleted(vector<``int``>& arr)``{` `    ``// Size of the array``    ``int` `N = arr.size();` `    ``// Minimum element``    ``auto` `it = *min_element(arr.begin(), arr.end());` `    ``// Finding frequency of minimum element``    ``int` `freq = 0;``    ``for` `(``auto` `x : arr) {``        ``if` `(x == it)``            ``freq++;``    ``}` `    ``return` `N - freq;``}` `// Driver Code``int` `main()``{``    ``vector<``int``> arr = { 3, 1, 1, 2, 4 };``    ``cout << elementsDeleted(arr);``}`

## Java

 `// Java code for the above approach``import` `java.util.*;` `class` `GFG{` `// Function to find the maximum number of``// elements that can be deleted from the array``static` `int` `elementsDeleted(``int` `[]arr)``{` `    ``// Size of the array``    ``int` `N = arr.length;` `    ``// Minimum element``    ``int` `it = Arrays.stream(arr).min().getAsInt();` `    ``// Finding frequency of minimum element``    ``int` `freq = ``0``;``    ``for` `(``int` `x : arr) {``        ``if` `(x == it)``            ``freq++;``    ``}` `    ``return` `N - freq;``}` `// Driver Code``public` `static` `void` `main(String[] args)``{``    ``int` `[]arr = { ``3``, ``1``, ``1``, ``2``, ``4` `};``    ``System.out.print(elementsDeleted(arr));``}``}` `// This code is contributed by 29AjayKumar`

## Python3

 `# Python code for the above approach` `# Function to find the maximum number of``# elements that can be deleted from the array``def` `elementsDeleted(arr):` `    ``# Size of the array``    ``N ``=` `len``(arr)` `    ``# Minimum element``    ``it ``=` `10``*``*``9` `    ``for` `i ``in` `range``(``len``(arr)):``        ``it ``=` `min``(it, arr[i])` `    ``# Finding frequency of minimum element``    ``freq ``=` `0``    ``for` `x ``in` `arr:``        ``if` `(x ``=``=` `it):``            ``freq ``+``=` `1``    ``return` `N ``-` `freq` `# Driver Code``arr ``=` `[``3``, ``1``, ``1``, ``2``, ``4``]``print``(elementsDeleted(arr))` `# This code is contributed by Saurabh jaiswal`

## C#

 `// C# code for the above approach``using` `System;``using` `System.Linq;``class` `GFG {` `    ``// Function to find the maximum number of``    ``// elements that can be deleted from the array``    ``static` `int` `elementsDeleted(``int``[] arr)``    ``{` `        ``// Size of the array``        ``int` `N = arr.Length;` `        ``// Minimum element``        ``int` `it = arr.Min();` `        ``// Finding frequency of minimum element``        ``int` `freq = 0;``        ``foreach``(``int` `x ``in` `arr)``        ``{``            ``if` `(x == it)``                ``freq++;``        ``}` `        ``return` `N - freq;``    ``}` `    ``// Driver Code``    ``public` `static` `void` `Main(``string``[] args)``    ``{``        ``int``[] arr = { 3, 1, 1, 2, 4 };``        ``Console.WriteLine(elementsDeleted(arr));``    ``}``}` `// This code is contributed by ukasp.`

## Javascript

 ``

Output

`3`

Time Complexity: O(N)
Auxiliary Space: O(1)

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