Program to find sum of elements in a given array

Given an array of integers, find sum of its elements.
Examples : 

Input : arr[] = {1, 2, 3}
Output : 6
1 + 2 + 3 = 6

Input : arr[] = {15, 12, 13, 10}
Output : 50

C++

/* C++ Program to find sum of elements
in a given array */
#include <bits/stdc++.h>
using namespace std;

// function to return sum of elements
// in an array of size n
int sum(int arr[], int n)
{
    int sum = 0; // initialize sum

    // Iterate through all elements
    // and add them to sum
    for (int i = 0; i < n; i++)
    sum += arr[i];

    return sum;
}

// Driver code
int main()
{
    int arr[] = {12, 3, 4, 15};
    int n = sizeof(arr) / sizeof(arr[0]);
    cout << "Sum of given array is " << sum(arr, n);
    return 0;
}

// This code is contributed by rathbhupendra

C

/* C Program to find sum of elements
 in a given array */
#include <bits/stdc++.h>

// function to return sum of elements
// in an array of size n
int sum(int arr[], int n)
{
    int sum = 0; // initialize sum

    // Iterate through all elements
    // and add them to sum
    for (int i = 0; i < n; i++)
    sum += arr[i];

    return sum;
}

int main()
{
    int arr[] = {12, 3, 4, 15};
    int n = sizeof(arr) / sizeof(arr[0]);
    printf("Sum of given array is %d", sum(arr, n));
    return 0;
}

Java

/* Java Program to find sum of elements in a given array  */
class Test
{
     static int arr[] = {12,3,4,15};

     // method for sum of elements in an array
     static int sum()
     {
         int sum = 0; // initialize sum
         int i;

         // Iterate through all elements and add them to sum
         for (i = 0; i < arr.length; i++)
            sum +=  arr[i];

         return sum;
     }

     // Driver method
     public static void main(String[] args)
     {
         System.out.println("Sum of given array is " + sum());
        }
 }

Python3

# Python 3 code to find sum
# of elements in given array
def _sum(arr,n):

    # return sum using sum
    # inbuilt sum() function
    return(sum(arr))

# driver function
arr=[]
# input values to list
arr = [12, 3, 4, 15]

# calculating length of array
n = len(arr)

ans = _sum(arr,n)

# display sum
print ('Sum of the array is ',ans)

# This code is contributed by Himanshu Ranjan

C#

// C# Program to find sum of elements in a
// given array
using System;

class GFG {

    // method for sum of elements in an array
    static int sum(int []arr, int n)
    {

        int sum = 0; // initialize sum

        // Iterate through all elements and
        // add them to sum
        for (int i = 0; i < n; i++)
            sum += arr[i];

        return sum;
    }

    // Driver method
    public static void Main()
    {

        int []arr = {12,3,4,15};
        int n = arr.Length;

        Console.Write("Sum of given array is "
                               + sum(arr, n));
    }

}

// This code is contributed by Sam007.

PHP

<?php
// PHP Program to find sum of
// elements in a given array

// function to return sum
// of elements in an array
// of size n
function sum( $arr, $n)
{
    // initialize sum
    $sum = 0;

    // Iterate through all elements
    // and add them to sum
    for ($i = 0; $i < $n; $i++)
    $sum += $arr[$i];

    return $sum;
}

// Driver Code
$arr =array(12, 3, 4, 15);
$n = sizeof($arr);
echo "Sum of given array is ",
                sum($arr, $n);

// This code is contributed by aj_36
?>

Javascript

<script>
//JavaScript Program to find
//sum of elements in a given array

    // function to return sum of elements
    // in an array of size n
    function sum(arr) {
        let sum = 0; // initialize sum

        // Iterate through all elements
        // and add them to sum
        for (let i = 0; i < arr.length; i++)
            sum += arr[i];

        return sum;
    }

    // Driver code
    let arr = [12, 3, 4, 15];
    document.write("Sum of given array is " + sum(arr));

 // This code is contributed by Surbhi Tyagi
</script>

Output

Sum of given array is 34

Time Complexity: O(n)

Auxiliary Space: O(1)

Another Method: Using STL
Calling inbuilt function for sum of elements of an array in STL.
accumulate(first, last, sum);
first, last : first and last elements of range  
                whose elements are to be added
sum :  initial value of the sum

This function returns the array sum.

C++

/* C++ Program to find sum of elements
in a given array */
#include <bits/stdc++.h>
using namespace std;

// Driver code
int main()
{
    int arr[] = {12, 3, 4, 15};
    int n = sizeof(arr) / sizeof(arr[0]);
      // calling accumulate function, passing first, last element and
    // initial sum, which is 0 in this case.
    cout << "Sum of given array is " << accumulate(arr, arr + n, 0);
    return 0;
}

// This code is contributed by pranoy_coder

Java

/* Java Program to find sum of elements
in a given array */
import java.util.*;

class GFG{

    static int accumulate(int []arr)
        {
            int sum = 0;
            for(int i = 0; i < arr.length; i++)
            {
                sum = sum + arr[i];
            }
            return sum;
        }

// Driver code
public static void main(String[] args)
{
    int arr[] = {12, 3, 4, 15};
    int n = arr.length;

      // calling accumulate function, passing first, last element and
    // initial sum, which is 0 in this case.
    System.out.print("Sum of given array is " +  accumulate(arr));
}
}

// This code is contributed by umadevi9616

Python3

# Python3 program to find sum of elements
# in a given array

# Driver code
if __name__ == "__main__":

    arr = [ 12, 3, 4, 15 ]
    n = len(arr)

    # Calling accumulate function, passing
    # first, last element and initial sum,
    # which is 0 in this case.
    print("Sum of given array is ", sum(arr));

# This code is contributed by ukasp

C#

/* C# Program to find sum of elements
in a given array */
using System;
public class GFG {

    static int accumulate(int[] arr) {
        int sum = 0;
        for (int i = 0; i < arr.Length; i++) {
            sum = sum + arr[i];
        }
        return sum;
    }

    // Driver code
    public static void Main(String[] args)
    {
        int []arr = { 12, 3, 4, 15 };
        int n = arr.Length;

        // calling accumulate function, passing first, last element and
        // initial sum, which is 0 in this case.
        Console.Write("Sum of given array is " + accumulate(arr));
    }
}

// This code is contributed by gauravrajput1

Javascript

<script>
     /* javascript Program to find sum of elements
    in a given array */

    function accumulate(arr)
    {
        let sum = 0;
        for(let i = 0; i < arr.length; i++)
        {
            sum = sum + arr[i];
        }
        return sum;
    }

    // Driver code

    let arr = [12, 3, 4, 15];
    let n = arr.length;

    // calling accumulate function, passing first, last element and
    // initial sum, which is 0 in this case
    document.write("Sum of given array is " + accumulate(arr));

    // This code is contributed by vaibhavrabadiya3.
</script>

Output

Sum of given array is 34

Time Complexity: O(n)

Auxiliary Space: O(1)

Another Method#2: Using Recursion

C++

/* C++ Program to find sum of elements
in a given array using recursion */
#include<iostream>
using namespace std;

// function to return sum of elements
// in an array of size n
int sum(int arr[],int n)
{
    //base case
    if(n==0){
        return 0;
    }
    else{
        //recursively calling the function
        return arr[0]+sum(arr+1,n-1);
    }
}
int main()
{
    int arr[] = {12, 3, 4, 15};
    int n=sizeof(arr)/sizeof(arr[0]);
    cout<<sum(arr,n);
    return 0;
    // This code is contributed by Shivesh Kumar Dwivedi
}

Java

/*package whatever //do not write package name here */
import java.io.*;
class GFG {

  static int sum(int[] arr, int n)
  {

    // base or terminating condition
    if (n <= 0) {
      return 0;
    }

    // Calling method recursively
    return sum(arr, n - 1) + arr[n - 1];
  }

  public static void main(String[] args)
  {

    int arr[] = { 12, 3, 4, 15 };
    int s = sum(arr, arr.length);

    System.out.println(s);
  }
}

Python3

# python Program to find sum of elements
# in a given array using recursion

# function to return sum of elements
# in an array of size n
def sum1(arr):
  if len(arr) == 1:
        return arr[0]
  else:
        return arr[0] + sum1(arr[1:])

arr = [12, 3, 4, 15]
print(sum1(arr))

# This code is contributed by laxmigangarajula03

C#

using System;

public class GFG {

  static int sum(int[] arr, int n)
  {
    // base or terminating condition
    if (n <= 0) {
      return 0;
    }

    // Calling method recursively
    return sum(arr, n-1 ) + arr[n-1];
  }

  public static void Main() {

    int []arr = {12, 3, 4, 15};
    int s = sum(arr, arr.Length);

    Console.Write(s);
  }

}

// This code is contributed by ksrikanth0498.

Output

34

Time Complexity: O(n)

Auxiliary Space: O(1)