根据数字的乘积对数字进行排序

给定N个非负整数的数组arr [] ，任务是根据它们的数字乘积对这些整数进行排序。

例子：

Input: arr[] = {12, 10, 102, 31, 15}
Output: 10 102 12 31 15
10 -> 1 * 0 = 0
102 -> 1 * 0 * 2 = 0
12 -> 1 * 2 = 2
31 -> 3 * 1 = 3
15 -> 1 * 5 = 5

Input: arr[] = {12, 10}
Output: 10 12

方法：这个想法是将每个元素及其数位乘积存储在向量对中，然后根据存储的数字积对向量的所有元素进行排序。最后，按顺序打印元素。

下面是上述方法的实现：

C++

// C++ implementation of the approach
#include 
using namespace std;
  
// Function to return the product
// of the digits of n
int productOfDigit(int n)
{
    int product = 1;
    while (n > 0) {
        product *= n % 10;
        n = n / 10;
    }
    return product;
}
  
// Function to sort the array according to
// the product of the digits of elements
void sortArr(int arr[], int n)
{
    // Vector to store the digit product
    // with respective elements
    vector > vp;
  
    // Inserting digit product with elements
    // in the vector pair
    for (int i = 0; i < n; i++) {
        vp.push_back(make_pair(productOfDigit(arr[i]), arr[i]));
    }
  
    // Sort the vector, this will sort the pair
    // according to the product of the digits
    sort(vp.begin(), vp.end());
  
    // Print the sorted vector content
    for (int i = 0; i < vp.size(); i++)
        cout << vp[i].second << " ";
}
  
// Driver code
int main()
{
    int arr[] = { 12, 10, 102, 31, 15 };
    int n = sizeof(arr) / sizeof(arr[0]);
  
    sortArr(arr, n);
  
    return 0;
}

Python3

# Python3 implementation of the approach 
  
# Function to return the product 
# of the digits of n 
def productOfDigit(n) :
  
    product = 1; 
    while (n > 0) :
        product *= (n % 10); 
        n = n // 10; 
  
    return product; 
  
# Function to sort the array according to 
# the product of the digits of elements 
def sortArr(arr, n) :
      
    # Vector to store the digit product 
    # with respective elements 
    vp = []; 
  
    # Inserting digit product with elements 
    # in the vector pair 
    for i in range(n) :
        vp.append((productOfDigit(arr[i]), arr[i])); 
      
    # Sort the vector, this will sort the pair 
    # according to the product of the digits 
    vp.sort(); 
  
    # Print the sorted vector content 
    for i in range(len(vp)) :
        print(vp[i][1], end = " "); 
  
# Driver code 
if __name__ == "__main__" : 
  
    arr = [ 12, 10, 102, 31, 15 ]; 
    n = len(arr); 
  
    sortArr(arr, n); 
  
# This code is contributed by AnkitRai01

输出：

10 102 12 31 15

时间复杂度： O(nlogn)