Product of all Subarrays of an Array

Given an array of integers arr of size N, the task is to print products of all subarrays of the array.

Examples:

Input: arr[] = {2, 4}
Output: 64
Here, subarrays are [2], [2, 4], [4]
Products are 2, 8, 4
Product of all Subarrays = 64

Input : arr[] = {10, 3, 7}
Output : 27783000
Here, subarrays are [10], [10, 3], [10, 3, 7], [3], [3, 7], [7]
Prodcuts are 10, 30, 210, 3, 21, 7
Product of all Subarrays = 27783000

Naive Approach: A simple solution is to generate all sub-array and compute their product.



C++

filter_none

edit
close

play_arrow

link
brightness_4
code

// C++ program to find product
// of all subarray of an array
  
#include <bits/stdc++.h>
using namespace std;
  
// Function to find product of all subarrays
void product_subarrays(int arr[], int n)
{
    // Variable to store the product
    int product = 1;
  
    // Compute the product while
    // traversing for subarrays
    for (int i = 0; i < n; i++) {
        for (int j = i; j < n; j++) {
            for (int k = i; k <= j; k++)
                product *= arr[k];
        }
    }
  
    // Printing product of all subarray
    cout << product << "\n";
}
  
// Driver code
int main()
{
    int arr[] = { 10, 3, 7 };
  
    int n = sizeof(arr) / sizeof(arr[0]);
  
    // Function call
    product_subarrays(arr, n);
  
    return 0;
}

chevron_right


Java

filter_none

edit
close

play_arrow

link
brightness_4
code

// Java program to find product
// of all subarray of an array
import java.util.*;
  
class GFG {
  
    // Function to find product of all subarrays
    static void product_subarrays(int arr[], int n)
    {
  
        // Variable to store the product
        int product = 1;
  
        // Compute the product while
        // traversing for subarrays
        for (int i = 0; i < n; i++) {
            for (int j = i; j < n; j++) {
                for (int k = i; k <= j; k++)
                    product *= arr[k];
            }
        }
  
        // Printing product of all subarray
        System.out.print(product + "\n");
    }
  
    // Driver code
    public static void main(String args[])
    {
        int arr[] = { 10, 3, 7 };
        int n = arr.length;
  
        // Function call
        product_subarrays(arr, n);
    }
}
  
// This code is contributed by shivanisinghss2110

chevron_right


Python3

filter_none

edit
close

play_arrow

link
brightness_4
code

# Python3 program to find product
# of all subarray of an array
  
# Function to find product of all subarrays
def product_subarrays(arr, n):
  
    # Variable to store the product
    product = 1;
  
    # Compute the product while
    # traversing for subarrays
    for i in range(0, n):
        for j in range(i, n):
            for k in range(i, j + 1):
                product *= arr[k];
          
    # Printing product of all subarray
    print(product, "\n");
  
# Driver code
arr = [ 10, 3, 7 ];
  
n = len(arr);
  
# Function call
product_subarrays(arr, n);
  
# This code is contributed by Code_Mech

chevron_right


C#

filter_none

edit
close

play_arrow

link
brightness_4
code

// C# program to find product
// of all subarray of an array
using System;
  
class GFG {
  
    // Function to find product of all subarrays
    static void product_subarrays(int[] arr, int n)
    {
  
        // Variable to store the product
        int product = 1;
  
        // Compute the product while
        // traversing for subarrays
        for (int i = 0; i < n; i++) {
            for (int j = i; j < n; j++) {
                for (int k = i; k <= j; k++)
                    product *= arr[k];
            }
        }
  
        // Printing product of all subarray
        Console.Write(product + "\n");
    }
  
    // Driver code
    public static void Main(String[] args)
    {
        int[] arr = { 10, 3, 7 };
        int n = arr.Length;
  
        // Function call
        product_subarrays(arr, n);
    }
}
  
// This code is contributed by shivanisinghss2110

chevron_right


Output:

27783000

Efficient Approach: An efficient approach is to use two loops and calculate the products while traversing for the subarrays.

Below is the implementation of the above approach:

C++

filter_none

edit
close

play_arrow

link
brightness_4
code

// C++ program to find product
// of all subarray of an array
  
#include <bits/stdc++.h>
using namespace std;
  
// Function to find product of all subarrays
void product_subarrays(long long int arr[], int n)
{
    // Variable to store the product
    long long int res = 1;
  
    // Compute the product while
    // traversing for subarrays
    for (int i = 0; i < n; i++) {
        long long int product = 1;
        for (int j = i; j < n; j++) {
            product = product * arr[j];
            res *= product;
        }
    }
    // Printing product of all subarray
    cout << res << "\n";
}
  
// Driver code
int main()
{
    long long int arr[] = { 10, 3, 7 };
  
    int n = sizeof(arr) / sizeof(arr[0]);
  
    // Function call
    product_subarrays(arr, n);
  
    return 0;
}

chevron_right


Java

filter_none

edit
close

play_arrow

link
brightness_4
code

// Java program to find product
// of all subarray of an array
import java.util.*;
  
class GFG {
  
    // Function to find product of all subarrays
    static void product_subarrays(int arr[], int n)
    {
        // Variable to store the product
        int res = 1;
  
        // Compute the product while
        // traversing for subarrays
        for (int i = 0; i < n; i++) {
            int product = 1;
            for (int j = i; j < n; j++) {
                product = product * arr[j];
                res *= product;
            }
        }
  
        // Printing product of all subarray
        System.out.println(res + "\n");
    }
  
    // Driver code
    public static void main(String args[])
    {
        int arr[] = { 10, 3, 7 };
  
        int n = arr.length;
  
        // Function call
        product_subarrays(arr, n);
    }
}
  
// This code is contributed by AbhiThakur

chevron_right


Python3

filter_none

edit
close

play_arrow

link
brightness_4
code

# Python3 program to find product
# of all subarray of an array
  
# Function to find product of all subarrays
def product_subarrays(arr, n):
  
    # Variable to store the product
    res = 1;
  
    # Compute the product while
    # traversing for subarrays
    for i in range(n):
        product = 1
        for j in range(i, n):
            product *= arr[j];
            res = res * product
  
    # Printing product of all subarray
    print(res);
  
# Driver code
if __name__ == '__main__':
    arr = [ 10, 3, 7 ];
  
    n = len(arr);
  
    # Function call
    product_subarrays(arr, n);
  
# This code is contributed by Princi Singh

chevron_right


C#

filter_none

edit
close

play_arrow

link
brightness_4
code

// C# program to find product
// of all subarray of an array
using System;
  
class GFG {
  
    // Function to find product of all subarrays
    static void product_subarrays(int[] arr, int n)
    {
        // Variable to store the product
        int res = 1;
  
        // Compute the product while
        // traversing for subarrays
        for (int i = 0; i < n; i++) {
            int product = 1;
            for (int j = i; j < n; j++) {
                product *= arr[j];
                res = res * product;
            }
        }
  
        // Printing product of all subarray
        Console.WriteLine(res + "\n");
    }
  
    // Driver code
    public static void Main(String[] args)
    {
        int[] arr = { 10, 3, 7 };
  
        int n = arr.Length;
  
        // Function call
        product_subarrays(arr, n);
    }
}
  
// This code is contributed by 29AjayKumar

chevron_right


Output:

27783000

Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready.




My Personal Notes arrow_drop_up

Check out this Author's contributed articles.

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.



Article Tags :
Practice Tags :


10


Please write to us at contribute@geeksforgeeks.org to report any issue with the above content.