📜  数组所有子数组的乘积

📅  最后修改于: 2021-05-07 09:17:23             🧑  作者: Mango

给定大小为N的整数arr数组,任务是打印该数组所有子数组的乘积。
例子:

天真的方法:一个简单的解决方案是生成所有子数组并计算其乘积。

C++
// C++ program to find product
// of all subarray of an array
 
#include 
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;
}


Java
// 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


Python3
# 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


C#
// 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


Javascript


C++
// C++ program to find product
// of all subarray of an array
 
#include 
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;
}


Java
// 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


Python3
# 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


C#
// 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


输出:
27783000

高效方法:一种高效方法是使用两个循环并在遍历子数组时计算乘积。
下面是上述方法的实现:

C++

// C++ program to find product
// of all subarray of an array
 
#include 
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;
}

Java

// 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

Python3

# 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

C#

// 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
输出:
27783000