Given an array of integers, find the sum of its elements.
Examples:
Input : arr[] = {1, 2, 3}
Output : 6
Explanation: 1 + 2 + 3 = 6
Input : 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++
#include <iostream>
using namespace std;
int sum( int arr[], int n)
{
if (n == 0) {
return 0;
}
else {
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
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int sum( int arr[], int n)
{
if (n == 0) {
return 0;
}
else {
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;
}
|
Java
import java.io.*;
class GFG {
static int sum( int [] arr, int n)
{
if (n <= 0 ) {
return 0 ;
}
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
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))
|
C#
using System;
public class GFG {
static int sum( int [] arr, int n)
{
if (n <= 0) {
return 0;
}
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);
}
}
|
Javascript
function sum(let arr, let n)
{
if (n <= 0) {
return 0;
}
return sum(arr, n-1 ) + arr[n-1];
}
let arr = {12, 3, 4, 15};
let s = sum(arr, arr.length);
document.write(s);
|
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
#include <bits/stdc++.h>
int sum( int arr[], int n)
{
int sum = 0;
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++
#include <bits/stdc++.h>
using namespace std;
int sum( int arr[], int n)
{
int sum = 0;
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]);
cout << "Sum of given array is " << sum(arr, n);
return 0;
}
|
Java
class Test {
static int arr[] = { 12 , 3 , 4 , 15 };
static int sum()
{
int sum = 0 ;
int i;
for (i = 0 ; i < arr.length; i++)
sum += arr[i];
return sum;
}
public static void main(String[] args)
{
System.out.println( "Sum of given array is "
+ sum());
}
}
|
Python3
def _sum(arr, n):
return ( sum (arr))
arr = []
arr = [ 12 , 3 , 4 , 15 ]
n = len (arr)
ans = _sum(arr, n)
print ( 'Sum of the array is ' , ans)
|
C#
using System;
class GFG {
static int sum( int [] arr, int n)
{
int sum = 0;
for ( int i = 0; i < n; i++)
sum += arr[i];
return sum;
}
public static void Main()
{
int [] arr = { 12, 3, 4, 15 };
int n = arr.Length;
Console.Write( "Sum of given array is "
+ sum(arr, n));
}
}
|
Javascript
<script>
function sum(arr) {
let sum = 0;
for (let i = 0; i < arr.length; i++)
sum += arr[i];
return sum;
}
let arr = [12, 3, 4, 15];
document.write( "Sum of given array is " + sum(arr));
</script>
|
PHP
<?php
function sum( $arr , $n )
{
$sum = 0;
for ( $i = 0; $i < $n ; $i ++)
$sum += $arr [ $i ];
return $sum ;
}
$arr = array (12, 3, 4, 15);
$n = sizeof( $arr );
echo "Sum of given array is " ,
sum( $arr , $n );
?>
|
OutputSum 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++
#include <bits/stdc++.h>
using namespace std;
int main()
{
int arr[] = { 12, 3, 4, 15 };
int n = sizeof (arr) / sizeof (arr[0]);
cout << "Sum of given array is "
<< accumulate(arr, arr + n, 0);
return 0;
}
|
Python3
if __name__ = = "__main__" :
arr = [ 12 , 3 , 4 , 15 ]
n = len (arr)
print ( "Sum of given array is " , sum (arr))
|
OutputSum of given array is 34
Time Complexity: O(n)
Auxiliary Space: O(1)
.