C program to Calculate Average of an Array

Write a C program to calculate average of an array using for loop. In this c example, the for loop iterate all array elements and calculate the sum. Next, we calculate the average by dividing the sum with array size.

#include <stdio.h>

int main()
{
	int Size, i, sum = 0;
	float avg = 0;

	printf("Please Enter the Array size = ");
	scanf("%d", &Size);

	int arr[Size];

	printf("Enter the Array Elements : ");
	for (i = 0; i < Size; i++)
	{
		scanf("%d", &arr[i]);
	}

	for (i = 0; i < Size; i++)
	{
		sum = sum + arr[i];
	}

	avg = (float)sum / Size;

	printf("\nThe Sum of Array Elements     = %d\n", sum);
	printf("\nThe Average of Array Elements = %.2f\n", avg);
}

Please Enter the Array size = 10
Enter the Array Elements : 22 44 66 88 99 111 123 133 144 155

The Sum of Array Elements     = 985

The Average of Array Elements = 98.50

In this array average example, we removed the extra for loop. Then, we performed the addition while inserting or reading the array elements.

#include <stdio.h>

int main()
{
	int Size, sum = 0;
	float avg = 0;

	printf("Please Enter the Array size = ");
	scanf("%d", &Size);

	int arr[Size];

	printf("Enter the Array Elements : ");
	for (int i = 0; i < Size; i++)
	{
		scanf("%d", &arr[i]);
		sum = sum + arr[i];
	}

	avg = (float)sum / Size;

	printf("\nThe Sum of Array Elements     = %d\n", sum);
	printf("\nThe Average of Array Elements = %.2f\n", avg);
}

C program to Calculate Average of an Array using a while loop

#include <stdio.h>

int main()
{
	int Size, sum = 0;
	float avg = 0;

	printf("Please Enter the size = ");
	scanf("%d", &Size);

	int arr[Size];

	printf("Enter the Elements : ");
	int i = 0; 
	while(i < Size)
	{
		scanf("%d", &arr[i]);
		sum = sum + arr[i];
		i++;
	}

	avg = (float)sum / Size;

	printf("\nThe Sum of Array Elements     = %d\n", sum);
	printf("\nThe Average of Array Elements = %.2f\n", avg);
}

Please Enter the size = 7
Enter the Elements : 19 29 39 49 59 79 89

The Sum of Array Elements     = 363

The Average of Array Elements = 51.86

In this C program, the arrayAverage function accepts the C array and its size and calculates the average of elements.

#include <stdio.h>

float arrayAverage(int arr[], int Size)
{
	int sum = 0;
	float avg = 0;

	for (int i = 0; i < Size; i++)
	{
		sum = sum + arr[i];
	}

	printf("\nThe Sum     = %d\n", sum);

	avg = (float)sum / Size;
	return avg;
}

int main()
{
	int Size;

	printf("Please Enter the size = ");
	scanf("%d", &Size);

	int arr[Size];

	printf("Enter the Elements : ");
	for (int i = 0; i < Size; i++)
	{
		scanf("%d", &arr[i]);
	}

	float avg = arrayAverage(arr, Size);
	
	printf("\nThe Average = %.2f\n", avg);
}

Please Enter the size = 8
Enter the Elements : 22 99 66 44 567 65 11 67

The Sum     = 941

The Average = 117.62

Average of an array using recursion

In the program below, we call the function recursively to add every element in an array and divide by the total number of array items to calculate the array average.

#include <stdio.h>
float findArrAvg(int a[], int n)
{
  if (n == 1)
  {
    return a[0];
  }
  return (a[n - 1] + (n - 1) * findArrAvg(a, n - 1)) / n;
}
int main()
{
  int arr[] = {10, 20, 30, 40};
  int size = sizeof(arr) / sizeof(arr[0]);

  printf("Array Average = %.2f", findArrAvg(arr, size));
}

Array Average = 25.00

Also Read

• C Program to Count Occurrence of an Element in an Array
• C Program to Count Frequency of each Element in an Array