# Functions Exercises

## C program to find sum of array elements using recursion

Write a C program to find sum of array elements using recursion. How to find sum of array elements using recursive function in C programming. Logic to find sum of array elements using recursion in C program.

#### Required knowledge

Basic C programming,c-Arrays, If else,for loop,Functions, Recursion

#### Program to print sum of array elements using recursion

```

/**
* C program to find sum of array elements using recursion
*/

#include <stdio.h>
#define MAX_SIZE 100

/* Function declaration to find sum of array */
int sum(int arr[], int start, int len);

int main()
{
int arr[MAX_SIZE];
int N, i, sumofarray;

/* Input size and elements in array  */
printf("Enter size of the array: ");
scanf("%d", &N);
printf("Enter elements in the array: ");
for(i=0; i<N; i++)
{
scanf("%d", &arr[i]);
}

sumofarray = sum(arr, 0, N);
printf("Sum of array elements: %d", sumofarray);

return 0;
}

/**
* Recursively find the sum of elements in an array.
*/
int sum(int arr[], int start, int len)
{
/* Recursion base condition */
if(start >= len)
return 0;

return (arr[start] + sum(arr, start + 1, len));
}

```

#### Output

Enter size of the array: 10

Enter elements in the array: 1 2 3 4 5 6 7 8 9 10

Sum of array elements: 55