Program for multiplication of array elements

We are given an array, and we have to calculate the product of an array using both iterative and recursive methods. 

Examples:

Input : array[] = {1, 2, 3, 4, 5, 6}
Output : 720
Here, product of elements = 1*2*3*4*5*6 = 720

Input : array[] = {1, 3, 5, 7, 9}
Output : 945 

Iterative Method: We initialize result as 1. We traverse array from left to right and multiply elements with results. 

Implementation:

C++

// Iterative C++ program to
// multiply array elements
#include<bits/stdc++.h>

using namespace std;

// Function to calculate the
// product of the array
int multiply(int array[], int n)
{
    int pro = 1;
    for (int i = 0; i < n; i++)
        pro = pro * array[i];
    return pro;
}

// Driver Code
int main()
{
    int array[] = {1, 2, 3, 4, 5, 6};
    int n = sizeof(array) / sizeof(array[0]);

    // Function call to calculate product
    cout << multiply(array, n);
    return 0;
}

Java

// Iterative Java program to
// multiply array elements
class GFG
{
    static int arr[] = {1, 2, 3, 4, 5, 6};

    // Method to calculate the
    // product of the array
    static int multiply()
    {
        int pro = 1;
        for (int i = 0; i < arr.length; i++)
            pro = pro * arr[i];
        return pro;
    }

    // Driver Code
    public static void main(String[] args)
    {
        // Method call to calculate product
        System.out.println(multiply());
        }
}

Python3

# Iterative Python3 code to
# multiply list elements

# Function to calculate
# the product of the array
def multiply( array , n ):
    pro = 1
    for i in range(n):
        pro = pro * array[i]
    return pro

# Driver code
array = [1, 2, 3, 4, 5, 6]
n = len(array)

# Function call to
# calculate product
print(multiply(array, n))

# This code is contributed
# by "Sharad_Bhardwaj".

C#

// Iterative C# program to
// multiply array elements
using System;

class GFG
{
    static int []arr = {1, 2, 3, 4, 5, 6};

    // Method to calculate the
    // product of the array
    static int multiply()
    {
        int pro = 1;
        for (int i = 0; i < arr.Length; i++)
            pro = pro * arr[i];
        return pro;
    }

    // Driver Code
    public static void Main()
    {
        // Method call to calculate product
        Console.Write(multiply());
    }
}

// This code is contributed by nitin mittal

PHP

<?php
// Iterative PHP program to
// multiply array elements


// Function to calculate the
// product of the array
function multiply($arr, $n)
{
    $pro = 1;
    for ($i = 0; $i < $n; $i++)
        $pro = $pro * $arr[$i];
    return $pro;
}

// Driver Code
$arr = array(1, 2, 3, 4, 5, 6);
$n = sizeof($arr) / sizeof($arr[0]);

// Function call to
// calculate product
echo multiply($arr, $n);
return 0;

// This code is contributed by nitin mittal.
?>

Javascript

<script>

// Iterative javascript program to
// multiply array elements

    var arr = [ 1, 2, 3, 4, 5, 6 ];

    // Method to calculate the
    // product of the array
    function multiply() {
        var pro = 1;
        for (i = 0; i < arr.length; i++)
            pro = pro * arr[i];
        return pro;
    }

    // Driver Code

        // Method call to calculate product
        document.write(multiply());

// This code contributed by aashish1995

</script>

Output

720

Time Complexity: O(n)
Auxiliary Space: O(1)

Recursive Method:

C++

// Recursive C++ program to
// multiply array elements
#include<iostream>

using namespace std;

// Function to calculate the
// product of array using recursion
int multiply(int a[], int n)
{
    // Termination condition
    if (n == 0)
        return(a[n]);
    else
        return (a[n] * multiply(a, n - 1));
}

// Driver Code
int main()
{
    int array[] = {1, 2, 3, 4, 5, 6};
    int n = sizeof(array) / sizeof(array[0]);

    // Function call to
    // calculate the product
    cout << multiply(array, n - 1)
         << endl;
    return 0;
}

Java

// Recursive Java program to
// multiply array elements
class GFG
{
    static int arr[] = {1, 2, 3, 4, 5, 6};

    // Method to calculate the product
    // of the array using recursion
    static int multiply(int a[], int n)
    {
        // Termination condition
        if (n == 0)
            return(a[n]);
        else
            return (a[n] * multiply(a, n - 1));
    }

    // Driver Code
    public static void main(String[] args)
    {
        // Method call to
        // calculate product
        System.out.println(multiply(arr,
                       arr.length - 1));
        }
}

Python3

# Recursive Python3 code
# to multiply array elements

# Function to calculate the product
# of array using recursion
def multiply( a , n ):

    # Termination condition
    if n == 0:
        return(a[n])
    else:
        return (a[n] * multiply(a, n - 1))

# Driver Code
array = [1, 2, 3, 4, 5, 6]
n = len(array)

# Function call to
# calculate the product
print(multiply(array, n - 1))

# This code is contributed
# by "Sharad_Bhardwaj".

C#

// Recursive C# program to
// multiply array elements
using System;

class GFG
{

    static int []arr = {1, 2, 3, 4, 5, 6};

    // Method to calculate the product
    // of the array using recursion
    static int multiply(int []a, int n)
    {

        // Termination condition
        if (n == 0)
            return(a[n]);
        else
            return (a[n] * multiply(a, n - 1));
    }

    // Driver Code
    public static void Main()
    {

        // Method call to
        // calculate product
        Console.Write(multiply(arr,
                               arr.Length - 1));
    }
}

// This code is contributed by Nitin Mittal.

PHP

<?php
// Recursive PHP program to
// multiply array elements

// Function to calculate the
// product of array using recursion
function multiply( $a, $n)
{
    // Termination condition
    if ($n == 0)
        return($a[$n]);
    else
        return ($a[$n] *
                 multiply($a, $n - 1));
}

// Driver Code
$array = array(1, 2, 3, 4, 5, 6);
$n = count($array);

// Function call to
// calculate the product
echo multiply($array, $n - 1)

// This code is contributed by anuj_67.
?>

Javascript

<script>
// Recursive javascript program to
// multiply array elements

    var arr = [ 1, 2, 3, 4, 5, 6 ];

    // Method to calculate the product
    // of the array using recursion
    function multiply(a , n) {
        // Termination condition
        if (n == 0)
            return (a[n]);
        else
            return (a[n] * multiply(a, n - 1));
    }

    // Driver Code

        // Method call to
        // calculate product
        document.write(multiply(arr,
                       arr.length - 1));

// This code is contributed by todaysgaurav
</script>

Output

720

Time Complexity: O(n)
Auxiliary Space: O(n)

Using C++ STL:

C++

// C++ program for multiplication of array elements
#include <iostream>
/*In C++, we can quickly find array product using
accumulate() and multiplies<>() defined in numeric library*/
#include <numeric>

using namespace std;

// Function to calculate the
// product of the array
int multiply(int array[], int n)
{
//The pro specifies the initial value to be considered
    int pro = 1;
/*
Here accumulate() take 4 parameters:
begening of array, end of array, the initial value
and the binary operation function object that will be applied
*/
    return accumulate(array, array + n, pro, multiplies<int>());
}

int main()
{
    int array[] = {1, 2, 3, 4, 5, 6};
    //get length of array
    int n = sizeof(array) / sizeof(array[0]);
    cout << multiply(array, n);
    return 0;
//This code is contributed by Shivesh Kumar Dwivedi
}

Output

720

Time Complexity: O(n)
Auxiliary Space: O(1)

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