Program to find sum of elements in a given array
Last Updated :
20 Sep, 2024
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Given an array of integers, find the sum of its elements.
Examples:
Input : arr[] = {1, 2, 3}
Output : 6
Explanation: 1 + 2 + 3 = 6Input : arr[] = {15, 12, 13, 10}
Output : 50
Sum of elements of an array using Recursion:
The idea is to use recursive approach which calculates the sum of an array by breaking it down into two cases: the base case, where if the array is empty the sum is 0; and the recursive case, where the sum is calculated by adding the first element to the sum of the remaining elements which is computed through a recursive call with the array shifted by one position and size reduced by one.
Below is the implementation of the above approach:
/* 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;
}
/* C++ Program to find sum of elements
in a given array using recursion */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
// 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]);
printf("%d", sum(arr, n));
return 0;
}
/*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);
}
}
# 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
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.
function sum(let arr, let n)
{
// base or terminating condition
if (n <= 0) {
return 0;
}
// Calling method recursively
return sum(arr, n-1 ) + arr[n-1];
}
let arr = {12, 3, 4, 15};
let s = sum(arr, arr.length);
document.write(s);
Output
34
Time Complexity: O(n)
Auxiliary Space: O(n), Recursive stack space
Sum of elements of an array using Iteration:
The idea is to iterate through each element of the array and adding it to a variable called sum. The sum variable is initialized to 0 before the iteration starts. After the iteration, the final sum is returned.
Below is the implementation of the above approach:
/* 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;
}
/* 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
/* 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());
}
}
# Function to return sum of
# elements in an array
def sum_array(arr):
total = 0 # initialize sum
# Iterate through all elements
# and add them to total
for num in arr:
total += num
return total
# Driver code
arr = [12, 3, 4, 15]
print("Sum of given array is", sum_array(arr))
// 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.
//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];
console.log("Sum of given array is " + sum(arr));
// This code is contributed by Surbhi Tyagi
<?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
?>
Output
Sum of given array is 34
Time Complexity: O(n)
Auxiliary Space: O(1)
Sum of elements of an array using Inbuild Methods:
The idea is to make use of built-in functions to find the sum of elements in a given array. These functions eliminate the need for explicit iteration, enhancing code simplicity.
Below is the implementation of above approach:
/* 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
import java.util.Arrays;
public class GFG {
// Driver code
public static void main(String[] args) {
int[] arr = {12, 3, 4, 15};
int sum = Arrays.stream(arr).sum();
System.out.println("Sum of given array is " + sum);
}
}
# 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# Program to find sum of elements in a
// given array
using System;
using System.Linq;
class GFG {
// Driver method
public static void Main()
{
int[] arr = { 12, 3, 4, 15 };
int n = arr.Length;
// calling LINQ Sum method on the array
// to calculate the sum of elements in an array
int sum = arr.Sum();
Console.Write("Sum of given array is " + sum);
}
}
// This code is contributed by abhishekmaran_.
// JavaScript program to find the sum of elements
// in a given array
// Driver code
const arr = [12, 3, 4, 15];
const n = arr.length;
// Calling the built-in reduce function to calculate the sum of elements in the array.
const sumOfArray = arr.reduce((accumulator, currentValue) => accumulator + currentValue, 0);
console.log("Sum of given array is ", sumOfArray);
// This code is contributed by Yash Agarwal(yashagarwal2852002)
Output
Sum of given array is 34
Time Complexity: O(n)
Auxiliary Space: O(1)
