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📜  通过对数字以降序排列的数组元素的最接近完美平方进行排序来修改数组

📅  最后修改于: 2021-04-17 15:08:48             🧑  作者: Mango

给定大小为N ( 1≤N≤10 5 )的数组arr [] ,任务是按降序对每个数组元素的数字进行排序,并用最接近的完美正方形替换每个数组元素,然后按升序打印该数组。

例子:

方法:请按照以下步骤解决问题:

  • 遍历数组arr []并对每个数组元素执行以下操作。
    • 将它们转换为等效的字符串表示形式。
    • 按降序对字符串进行排序。
    • 将字符串转换回其等效整数。
    • 找到当前数组元素的最接近的理想平方
  • 现在,以升序对数组进行排序。
  • 打印排序后的数组。

下面是上述方法的实现。

C++
// C++ program of the above approach
 
#include 
using namespace std;
 
// Function to sort array in ascending order
// after replacing array elements by nearest
// perfect square of decreasing order of digits
void sortArr(int arr[], int N)
{
 
    // Traverse the array of strings
    for (int i = 0; i < N; i++) {
 
        // Convert the current array
        // element to a string
        string s = to_string(arr[i]);
 
        // Sort each string in descending order
        sort(s.begin(), s.end(), greater());
 
        // Convert the string to
        // equivalent integer
        arr[i] = stoi(s);
 
        // Calculate square root of
        // current array element
        int sr = sqrt(arr[i]);
 
        // Calculate perfect square
        int a = sr * sr;
        int b = (sr + 1) * (sr + 1);
 
        // Find the nearest perfect square
        if ((arr[i] - a) < (b - arr[i]))
            arr[i] = a;
        else
            arr[i] = b;
    }
 
    // Sort the array in ascending order
    sort(arr, arr + N);
 
    // Print the array
    for (int i = 0; i < N; i++) {
        cout << arr[i] << " ";
    }
}
 
// Driver Code
int main()
{
    int arr[] = { 29, 43, 28, 12 };
    int N = sizeof(arr) / sizeof(arr[0]);
    sortArr(arr, N);
 
    return 0;
}


Java
// Java program for the above approach
import java.util.*;
 
class GFG{
  static void reverse(char[] a) 
  {
    int i, n = a.length;
    char t;
    for (i = 0; i < n / 2; i++) 
    {
      t = a[i];
      a[i] = a[n - i - 1];
      a[n - i - 1] = t;
    }
  }
 
  // Function to sort array in ascending order
  // after replacing array elements by nearest
  // perfect square of decreasing order of digits
  static void sortArr(int arr[], int N)
  {
 
    // Traverse the array of strings
    for (int i = 0; i < N; i++) {
 
      // Convert the current array
      // element to a string
      String s = Integer.toString(arr[i]);
      char[] str = s.toCharArray();
 
      // Sort each string in descending order
      Arrays.sort(str);
      reverse(str);
 
      String string = new String(str);
 
 
      // Convert the string to
      // equivalent integer
      arr[i] = Integer.parseInt(string);
 
      // Calculate square root of
      // current array element
      int sr = (int)Math.sqrt(arr[i]);
 
      // Calculate perfect square
      int a = sr * sr;
      int b = (sr + 1) * (sr + 1);
 
      // Find the nearest perfect square
      if ((arr[i] - a) < (b - arr[i]))
        arr[i] = a;
      else
        arr[i] = b;
    }
 
    // Sort the array in ascending order
    Arrays.sort(arr);
 
    // Print the array
    for (int i = 0; i < N; i++) {
      System.out.print(arr[i] + " ");
    }
  }
 
 
  // Driver Code
  public static void main(String[] args)
  {
    int arr[] = { 29, 43, 28, 12 };
    int N = arr.length;
    sortArr(arr, N);
  }
}
 
// This code is contributed by sanjoy_62.


Python3
# Python 3 program of the above approach
import math
 
# Function to sort array in ascending order
# after replacing array elements by nearest
# perfect square of decreasing order of digits
def sortArr(arr, N):
 
    # Traverse the array of strings
    for i in range(N):
 
        # Convert the current array
        # element to a string
        s = str(arr[i])
 
        # Sort each string in descending order
        list1 = list(s)
        list1.sort(reverse = True)
        s = ''.join(list1)
 
        # Convert the string to
        # equivalent integer
        arr[i] = int(s)
 
        # Calculate square root of
        # current array element
        sr = int(math.sqrt(arr[i]))
 
        # Calculate perfect square
        a = sr * sr
        b = (sr + 1) * (sr + 1)
 
        # Find the nearest perfect square
        if ((arr[i] - a) < (b - arr[i])):
            arr[i] = a
        else:
            arr[i] = b
 
    # Sort the array in ascending order
    arr.sort()
 
    # Print the array
    for i in range(N):
        print(arr[i], end=" ")
 
# Driver Code
if __name__ == "__main__":
 
    arr = [29, 43, 28, 12]
    N = len(arr)
    sortArr(arr, N)
 
    # This code is contributed by ukasp.


C#
// C# program of the above approach
 
using System;
using System.Collections.Generic;
 
class GFG{
 
  // Function to sort array in ascending order
  // after replacing array elements by nearest
  // perfect square of decreasing order of digits
  static void sortArr(int []arr, int N)
  {
 
    // Traverse the array of strings
    for (int i = 0; i < N; i++) {
 
      // Convert the current array
      // element to a string
      int num = arr[i];
      string s = num.ToString();
 
      // Sort each string in descending order
      char []temp = s.ToCharArray();
      Array.Sort(temp);
      int st = 0;
      int ed = temp.Length-1;
      while(st());
 
      // Convert the string to
      // equivalent integer
      arr[i] = Int32.Parse(charsStr);
 
      // Calculate square root of
      // current array element
      int sr = (int)Math.Sqrt(arr[i]);
 
      // Calculate perfect square
      int a = sr * sr;
      int b = (sr + 1) * (sr + 1);
 
      // Find the nearest perfect square
      if ((arr[i] - a) < (b - arr[i]))
        arr[i] = a;
      else
        arr[i] = b;
    }
 
    // Sort the array in ascending order
    Array.Sort(arr);
 
    // Print the array
    for (int i = 0; i < N; i++) {
      Console.Write(arr[i]+" ");
    }
  }
 
  // Driver Code
  public static void Main()
  {
    int []arr = { 29, 43, 28, 12 };
    int N = arr.Length;
    sortArr(arr, N);
 
  }
}
 
// This code is contributed by ipg2016107.


输出:
25 49 81 100

时间复杂度: O(NlogN)
辅助空间: O(1)