# Program for average of an array (Iterative and Recursive)

• Difficulty Level : Medium
• Last Updated : 11 Oct, 2021

Given an array, the task is to find average of that array. Average is the sum of array elements divided by the number of elements.

Examples :

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```Input : arr[] = {1, 2, 3, 4, 5}
Output : 3
Sum of the elements is 1+2+3+4+5 = 15
and total number of elements is 5.
So average is 15/5 = 3

Input : arr[] = {5, 3, 6, 7, 5, 3}
Output : 4.83333
Sum of the elements is 5+3+6+7+5+3 = 29
and total number of elements is 6.
So average is 29/6 = 4.83333.```

Iterative:
Iterative program is easy. We need to find sum and divide sum by total number of elements.

## C++

 `// C++ program to calculate average of array elements``#include ``using` `namespace` `std;` `// Function that return average of an array.``double` `average(``int` `a[], ``int` `n)``{``    ``// Find sum of array element``    ``int` `sum = 0;``    ``for` `(``int` `i=0; i

## Java

 `// Java program to calculate average of array elements``class` `GFG {``    ` `    ``// Function that return average of an array.``    ``static` `double` `average(``int` `a[], ``int` `n)``    ``{``        ` `        ``// Find sum of array element``        ``int` `sum = ``0``;``        ` `        ``for` `(``int` `i = ``0``; i < n; i++)``            ``sum += a[i];``    ` `        ``return` `(``double``)sum / n;``    ``}``    ` `    ``//driver code``    ``public` `static` `void` `main (String[] args)``    ``{``        ` `        ``int` `arr[] = {``10``, ``2``, ``3``, ``4``, ``5``, ``6``, ``7``, ``8``, ``9``};``        ``int` `n = arr.length;``    ` `        ``System.out.println(average(arr, n));``    ``}``}` `// This code is contributed by Anant Agarwal.`

## Python3

 `# Python3 code to calculate``# average of array elements` `# Function that return``# average of an array.``def` `average( a , n ):` `    ``# Find sum of array element``    ``sum` `=` `0``    ``for` `i ``in` `range``(n):``        ``sum` `+``=` `a[i]``    ` `    ``return` `sum``/``n;` `# Driver code``arr ``=` `[``10``, ``2``, ``3``, ``4``, ``5``, ``6``, ``7``, ``8``, ``9``]``n ``=` `len``(arr)``print``(average(arr, n))` `# This code is contributed by "Shard_Bhardwaj".`

## C#

 `// C# program to calculate average of``// array elements``using` `System;``class` `GFG {``    ` `    ``// Function that return average of``    ``// an array.``    ``static` `double` `average(``int` `[]a, ``int` `n)``    ``{``        ` `        ``// Find sum of array element``        ``int` `sum = 0;``        ` `        ``for` `(``int` `i = 0; i < n; i++)``            ``sum += a[i];``    ` `        ``return` `(``double``)sum / n;``    ``}``    ` `    ``// Driver code``    ``public` `static` `void` `Main ()``    ``{``        ` `        ``int` `[]arr = {10, 2, 3, 4, 5, 6,``                                ``7, 8, 9};``        ``int` `n = arr.Length;``    ` `        ``Console.Write(average(arr, n));``    ``}``}` `// This code is contributed by nitin mittal.`

## PHP

 ``

## Javascript

 ``
Output
`6`

Time Complexity: O(n)

Recursive:
The idea is to pass index of element as an additional parameter and recursively compute sum. After computing sum, divide the sum by n.

## C++

 `// C++ program to calculate average of array elements``#include ``using` `namespace` `std;` `// Recursively computes average of a[]``double` `avgRec(``int` `a[], ``int` `i, ``int` `n)``{``    ``// Last element``    ``if` `(i == n-1)``        ``return` `a[i];` `    ``// When index is 0, divide sum computed so``    ``// far by n.``    ``if` `(i == 0)``        ``return` `((a[i] + avgRec(a, i+1, n))/n);` `    ``// Compute sum``    ``return` `(a[i] + avgRec(a, i+1, n));``}` `// Function that return average of an array.``double` `average(``int` `a[], ``int` `n)``{``     ``return` `avgRec(a, 0, n);``}` `// Driver code``int` `main()``{``    ``int` `arr[] = {10, 2, 3, 4, 5, 6, 7, 8, 9};``    ``int` `n = ``sizeof``(arr)/``sizeof``(arr);` `    ``cout << average(arr, n) << endl;``    ``return` `0;``}`

## Java

 `// Java program to calculate average``// of array elements` `class` `CalcAvg``{``    ``// Recursively computes average of a[]``    ``static` `double` `avgRec(``int` `a[], ``int` `i, ``int` `n)``    ``{``        ``// Last element``        ``if` `(i == n-``1``)``            ``return` `a[i];``     ` `        ``// When index is 0, divide sum computed so``        ``// far by n.``        ``if` `(i == ``0``)``            ``return` `((a[i] + avgRec(a, i+``1``, n))/n);``     ` `        ``// Compute sum``        ``return` `(a[i] + avgRec(a, i+``1``, n));``    ``}``     ` `    ``// Function that return average of an array.``    ``static` `double` `average(``int` `a[], ``int` `n)``    ``{``         ``return` `avgRec(a, ``0``, n);``    ``}``    ` `    ``// main function``    ``public` `static` `void` `main (String[] args)``    ``{``        ``int` `arr[] = {``10``, ``2``, ``3``, ``4``, ``5``, ``6``, ``7``, ``8``, ``9``};``        ``int` `n = arr.length;``     ` `        ``System.out.println(average(arr, n));``    ``}``}`

## Python3

 `# Python3 code to calculate``# average of array elements` `# Recursively computes average of a[]``def` `avgRec( a , i , n ):``    ` `    ``# Last element``    ``if` `i ``=``=` `n``-``1``:``        ``return` `a[i]``    ` `    ``# When index is 0, divide sum``    ``# computed so far by n.``    ``if` `i ``=``=` `0``:``        ``return` `((a[i] ``+` `avgRec(a, i``+``1``, n)) ``/` `n)``    ` `    ``# Compute sum``    ``return` `(a[i] ``+` `avgRec(a, i``+``1``, n))` `# Function that return``# average of an array.``def` `average(a, n):``    ``return` `avgRec(a, ``0``, n)` `# Driver code``arr ``=` `[``10``, ``2``, ``3``, ``4``, ``5``, ``6``, ``7``, ``8``, ``9``]``n ``=` `len``(arr)``print``(average(arr, n))` `# This code is contributed by "Sharad_Bhardwaj".`

## C#

 `// C# program to calculate average``// of array elements``using` `System;` `class` `GFG {``    ` `    ``// Recursively computes average of a[]``    ``static` `double` `avgRec(``int` `[]a, ``int` `i, ``int` `n)``    ``{``        ` `        ``// Last element``        ``if` `(i == n-1)``            ``return` `a[i];``    ` `        ``// When index is 0, divide sum``        ``// computed so far by n.``        ``if` `(i == 0)``            ``return` `((a[i] + avgRec(a, i+1, n))/n);``    ` `        ``// Compute sum``        ``return` `(a[i] + avgRec(a, i+1, n));``    ``}``    ` `    ``// Function that return average of an array.``    ``static` `double` `average(``int` `[]a, ``int` `n)``    ``{``        ``return` `avgRec(a, 0, n);``    ``}``    ` `    ``// main function``    ``public` `static` `void` `Main ()``    ``{``        ``int` `[]arr = {10, 2, 3, 4, 5, 6, 7, 8, 9};``        ``int` `n = arr.Length;``    ` `        ``Console.Write(average(arr, n));``    ``}``}` `// This code is contributed by Smitha.`

## PHP

 ``

## Javascript

 ``
Output
`6`

Related Article :
Average of a stream of numbers

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