选择 n 个元素，使其平均值最大
原文:https://www . geesforgeks . org/choose-n-elements-so-它们的平均值是最大值/
给定一个由 2 * n 个元素组成的数组，任务是构造并打印一个由 n 个元素组成的数组，使得新数组的均值最大。这里 n 是偶数。
示例:
输入: arr[] = {3，1，2，3，8，6} 输出:3 6 8 T6】输入: arr[] = {3，2，3，8} 输出: 3 8
方法:数组的平均值是同一数组元素的平均值，即 (∑arr[i]) / n 。因此，为了使数组的平均值最大，从数组中选择最大的 n 元素，这可以通过首先对数组进行排序，然后从最大值开始选择元素来实现。 以下是上述方法的实现:
C++
// C++ implementation of the approach
#include <bits/stdc++.h>
using namespace std;
// Utility function to print the contents
// of an array
void printArray(int arr[], int n)
{
for (int i = 0; i < n; i++)
cout << arr[i] << " ";
}
// Function to print the array with
// maximum mean
void printMaxMean(int arr[], int n)
{
int newArr[n];
// Sort the original array
sort(arr, arr + 2 * n);
// Construct new array
for (int i = 0; i < n; i++)
newArr[i] = arr[i + n];
// Print the resultant array
printArray(newArr, n);
}
// Driver code
int main()
{
int arr[] = { 4, 8, 3, 1, 3, 7, 0, 4 };
int n = sizeof(arr) / sizeof(arr[0]);
printMaxMean(arr, n / 2);
return 0;
}
Java 语言(一种计算机语言，尤用于创建网站)
// Java implementation of the approach
import java.util.Arrays;
class GfG{
// Utility function to print the
// contents of an array
static void printArray(int arr[], int n)
{
for (int i = 0; i < n; i++)
System.out.print(arr[i] + " ");
}
// Function to print the array
// with maximum mean
static void printMaxMean(int arr[], int n)
{
int newArr[] = new int[n];
// Sort the original array
Arrays.sort(arr, 0, 2 * n);
// Construct new array
for (int i = 0; i < n; i++)
newArr[i] = arr[i + n];
// Print the resultant array
printArray(newArr, n);
}
// Driver code
public static void main(String []args)
{
int arr[] = { 4, 8, 3, 1, 3, 7, 0, 4 };
int n = arr.length;
printMaxMean(arr, n / 2);
}
}
// This code is contributed by
// Rituraj Jain
Python 3
# Python3 implementation of the approach
# Utility function to print the contents
# of an array
def printArray(arr, n) :
for i in range(n) :
print(arr[i], end = " ")
# Function to print the array with
# maximum mean
def printMaxMean(arr, n) :
newArr = [0] * n
# Sort the original array
arr.sort()
# Construct new array
for i in range(n) :
newArr[i] = arr[i + n]
# Print the resultant array
printArray(newArr, n)
# Driver code
if __name__ == "__main__" :
arr = [ 4, 8, 3, 1, 3, 7, 0, 4 ]
n = len(arr)
printMaxMean(arr, n // 2)
# This code is contributed by Ryuga
C
// C# implementation of the approach
using System;
class GfG
{
// Utility function to print the
// contents of an array
static void printArray(int[] arr, int n)
{
for (int i = 0; i < n; i++)
Console.Write(arr[i] + " ");
}
// Function to print the array
// with maximum mean
static void printMaxMean(int[] arr, int n)
{
int[] newArr = new int[n];
// Sort the original array
Array.Sort(arr, 0, 2 * n);
// Construct new array
for (int i = 0; i < n; i++)
newArr[i] = arr[i + n];
// Print the resultant array
printArray(newArr, n);
}
// Driver code
public static void Main()
{
int[] arr = { 4, 8, 3, 1, 3, 7, 0, 4 };
int n = arr.Length;
printMaxMean(arr, n / 2);
}
}
// This code is contributed by Ita_c.
服务器端编程语言（Professional Hypertext Preprocessor 的缩写）
<?php
// PHP implementation of the approach
// Utility function to print the contents
// of an array
function printArray($arr, $n)
{
for ($i = 0; $i < $n; $i++)
echo $arr[$i] . " ";
}
// Function to print the array with
// maximum mean
function printMaxMean($arr, $n)
{
$newArr[$n] = array();
// Sort the original array
sort($arr,0);
// Construct new array
for ($i = 0; $i < $n; $i++)
$newArr[$i] = $arr[$i + $n];
// Print the resultant array
printArray($newArr, $n);
}
// Driver code
$arr = array(4, 8, 3, 1, 3, 7, 0, 4);
$n = sizeof($arr);
printMaxMean($arr, $n / 2);
// This code is contributed
// by Akanksha Rai
java 描述语言
<script>
// javascript implementation of the approach
// Utility function to print the
// contents of an array
function printArray(arr , n) {
for (i = 0; i < n; i++)
document.write(arr[i] + " ");
}
// Function to print the array
// with maximum mean
function printMaxMean(arr , n) {
var newArr = Array(n).fill(0);
// Sort the original array
arr.sort((a,b)=>a-b);
// Construct new array
for (i = 0; i < n; i++)
newArr[i] = arr[i + n];
// Print the resultant array
printArray(newArr, n);
}
// Driver code
var arr = [ 4, 8, 3, 1, 3, 7, 0, 4 ];
var n = arr.length;
printMaxMean(arr, n / 2);
// This code contributed by gauravrajput1
</script>
Output:
4 4 7 8
版权属于：月萌API www.moonapi.com，转载请注明出处
