对数组中的所有偶数进行排序，而不改变奇数元素的顺序

给定一个大小为N的数组arr[] ，任务是对数组中的所有偶数进行排序，而不改变奇数元素的顺序
例子：

Input: arr[] = {4, 7, 2, 11, 15}
Output: {2, 7, 4, 11, 15}
Explanation: Even numbers are sorted at their corresponding places, without changing the order of odd elements
 

Input: arr[] = {12, 6}
Output: {6, 12}

方法：可以通过将偶数元素分离到另一个容器中来解决该任务，例如“偶数”，对该容器进行排序，并在迭代数组时，将偶数元素替换为存储在偶数中的已排序偶数元素

下面是上述方法的实现：

C++

#include 
using namespace std;
 
// Function to get the required array
void solve(int arr[], int n)
{
 
    // Store even elements
    vector evens;
    for (int i = 0; i < n; i++) {
        if (arr[i] % 2 == 0)
            evens.push_back(arr[i]);
    }
 
    // Sort all even elements
    sort(evens.begin(), evens.end());
    int l = 0;
 
    // Placing even elements in sorted order
    for (int i = 0; i < n; i++) {
        if (arr[i] % 2 == 0)
            arr[i] = evens[l++];
    }
 
    // Updated array
    for (int i = 0; i < n; i++)
        cout << arr[i] << " ";
}
 
// Driver Code
int main()
{
    int N = 5;
    int arr[N] = { 4, 7, 2, 11, 15 };
    solve(arr, N);
    return 0;
}

Java

// Java program for the above approach
import java.util.*; 
 
public class GFG {
 
    // Function to get the required array
    static void solve(int []arr, int n)
    {
  
        // Store even elements
        ArrayList evens = new ArrayList();
        for (int i = 0; i < n; i++) {
            if (arr[i] % 2 == 0)
                evens.add(arr[i]);
        }
  
        // Sort all even elements
        Collections.sort(evens); 
 
        int l = 0;
         
        // Placing even elements in sorted order
        for (int i = 0; i < n; i++) {
            if (arr[i] % 2 == 0)
                arr[i] = evens.get(l++);
        }
  
        // Updated array
        for (int i = 0; i < n; i++)
            System.out.print(arr[i] + " ");
    }
 
    // Driver function
    public static void main(String []args)
    {
        int N = 5;
        int []arr = { 4, 7, 2, 11, 15 };
        solve(arr, N);
         
    }
}
 
// This code is contributed by AnkThon

Python3

# python program of the above approach
 
# Function to get the required array
def solve(arr, n):
 
        # Store even elements
    evens = []
    for i in range(0, n):
        if (arr[i] % 2 == 0):
            evens.append(arr[i])
 
        # Sort all even elements
    evens.sort()
    l = 0
 
    # Placing even elements in sorted order
    for i in range(0, n):
        if (arr[i] % 2 == 0):
            arr[i] = evens[l]
            l += 1
 
        # Updated array
    for i in range(0, n):
        print(arr[i], end=" ")
 
# Driver Code
if __name__ == "__main__":
 
    N = 5
    arr = [4, 7, 2, 11, 15]
    solve(arr, N)
 
    # This code is contributed by rakeshsahni

C#

// C# program for the above approach
using System;
using System.Collections.Generic;
 
class GFG {
 
    // Function to get the required array
    static void solve(int []arr, int n)
    {
  
        // Store even elements
        List evens = new List();
        for (int i = 0; i < n; i++) {
            if (arr[i] % 2 == 0)
                evens.Add(arr[i]);
        }
  
        // Sort all even elements
        evens.Sort();
        int l = 0;
         
        // Placing even elements in sorted order
        for (int i = 0; i < n; i++) {
            if (arr[i] % 2 == 0)
                arr[i] = evens[l++];
        }
  
        // Updated array
        for (int i = 0; i < n; i++)
            Console.Write(arr[i] + " ");
    }
 
    // Driver function
    public static void Main()
    {
        int N = 5;
        int []arr = new int[] { 4, 7, 2, 11, 15 };
        solve(arr, N);
         
    }
}
 
// This code is contributed by Samim Hossain Mondal

Javascript

// Javascript program for the above approach
 
// Function to get the required array
function solve(arr, n)
{
    // Store even elements
    let evens = [];
    for (let i = 0; i < n; i++) {
        if (arr[i] % 2 == 0)
            evens.push(arr[i]);
    }
  
    // Sort all even elements
    evens.sort();
    let l = 0;
  
    // Placing even elements in sorted order
    for (let i = 0; i < n; i++) {
        if (arr[i] % 2 == 0)
            arr[i] = evens[l++];
    }
  
    // Updated array
    for (let i = 0; i < n; i++)
        document.write(arr[i] + " ");
}
  
// Driver Code
  let N = 5;
  let arr = [ 4, 7, 2, 11, 15 ];
  solve(arr, N);
     
// This code is contributed by Samim Hossain Mondal.

输出

2 7 4 11 15 

时间复杂度：O(NlogN)
辅助空间：O(N)