Program for average of an array (Iterative and Recursive)
Last Updated :
21 Aug, 2022
Improve
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 :
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 <iostream>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<n; i++) sum += a[i]; return (double)sum/n;}// Driver codeint main(){ int arr[] = {10, 2, 3, 4, 5, 6, 7, 8, 9}; int n = sizeof(arr)/sizeof(arr[0]); cout << average(arr, n) << endl; return 0;} |
Java
// Java program to calculate average of array elementsclass 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 codearr = [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 elementsusing 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
<?php// PHP program to calculate average// of array elements// Function that return average of// an array.function average( $a, $n){ // Find sum of array element $sum = 0; for ( $i = 0; $i < $n; $i++) $sum += $a[$i]; return $sum / $n;}// Driver code $arr = array(10, 2, 3, 4, 5, 6, 7, 8, 9); $n = count($arr); echo average($arr, $n);// This code is contributed by anuj_67.?> |
Javascript
<script> // JavaScript program to calculate average of array elements // Function that return average of an array. function average(a, n) { // Find sum of array element var sum = 0; for (var i = 0; i < n; i++) sum += a[i]; return parseFloat(sum / n); } // Driver code var arr = [10, 2, 3, 4, 5, 6, 7, 8, 9]; var n = arr.length; document.write(average(arr, n)); document.write("<br>"); // This code is contributed by rdtank. </script> |
Output
6
Time Complexity: O(n)
Auxiliary Space: O(1)
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 <iostream>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 codeint main(){ int arr[] = {10, 2, 3, 4, 5, 6, 7, 8, 9}; int n = sizeof(arr)/sizeof(arr[0]); cout << average(arr, n) << endl; return 0;} |
Java
// Java program to calculate average // of array elementsclass 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 codearr = [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 elementsusing 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
<?php// PHP program to calculate // average of array elements// Recursively computes // average of a[]function 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, $n));}// Function that return // average of an array.function average($a, $n){ return avgRec($a, 0, $n);}// Driver code$arr = array(10, 2, 3, 4, 5, 6, 7, 8, 9);$n = sizeof($arr);echo average($arr, $n) ;// This code is contributed by Anuj_67?> |
Javascript
<script>// Java script program to calculate average// of array elements// Recursively computes average of a[]function 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.function average(a, n){ return avgRec(a, 0, n);}// Driver codelet arr = [ 10, 2, 3, 4, 5, 6, 7, 8, 9 ];let n = arr.length;document.write(average(arr, n));// This code is contributed by sravan kumar G</script> |
Output
6
Time Complexity: O(n)
Auxiliary Space: O(n)
Related Article :
Average of a stream of numbers
