Find the sum of the first half and second half elements of an array

25 May, 2022
Given an array arr of size N. The task is to find the sum of the first half (N/2) elements and second half elements (N – N/2) of an array.Examples: 
Input : arr[] = {20, 30, 60, 10, 25, 15, 40} Output : 110, 90 Sum of first N/2 elements 20 + 30 + 60 is 110Input : arr[] = {50, 35, 20, 15} Output : 85, 35
Approach: Initialize SumFirst and SumSecond as 0. Traverse the given array and add elements in SumFirst if the current index is less than N/2 otherwise add in SumSecond.Below is the implementation of the above approach: 
C++
Java
Python3
C#
Javascript
// C++ program to find the sum of the first half// elements and second half elements of an array#include <bits/stdc++.h>using namespace std; // Function to find the sum of the first half// elements and second half elements of an arrayvoid sum_of_elements(int arr[], int n){    int sumfirst = 0, sumsecond = 0;     for (int i = 0; i < n; i++) {        // Add elements in first half sum        if (i < n / 2)            sumfirst += arr[i];         // Add elements in the second half sum        else            sumsecond += arr[i];    }     cout << "Sum of first half elements is " <<                                   sumfirst << endl;     cout << "Sum of second half elements is " <<                                   sumsecond << endl;} // Driver Codeint main(){    int arr[] = { 20, 30, 60, 10, 25, 15, 40 };     int n = sizeof(arr) / sizeof(arr[0]);     // Function call    sum_of_elements(arr, n);     return 0;}
// Java program to count pairs// whose sum divisible by 'K'import java.util.*; class GFG{ public static void sum_of_elements(int []arr,                                   int n){    int sumfirst = 0, sumsecond = 0;         for (int i = 0; i < n; i++)    {                 // Add elements in first half sum        if (i < n / 2)        {            sumfirst += arr[i];        }                 // Add elements in the second half sum        else        {            sumsecond += arr[i];        }    }         System.out.println("Sum of first half elements is " +                                             sumfirst);         System.out.println("Sum of second half elements is " +                                            sumsecond);} // Driver codepublic static void main(String[] args){    int []arr = { 20, 30, 60, 10, 25, 15, 40 };    int n = arr.length;         // Function call    sum_of_elements(arr, n);}} // This code is contributed by Princi Singh
# Python3 program to find the sum of# the first half elements and# second half elements of an array # Function to find the sum of # the first half elements and# second half elements of an arraydef sum_of_elements(arr, n):     sumfirst = 0;    sumsecond = 0;     for i in range(n):                 # Add elements in first half sum        if (i < n // 2):            sumfirst += arr[i];         # Add elements in the second half sum        else:            sumsecond += arr[i];                 print("Sum of first half elements is",                    sumfirst, end = "\n");    print("Sum of second half elements is",                    sumsecond, end = "\n"); # Driver Codearr = [20, 30, 60, 10, 25, 15, 40]; n = len(arr); # Function callsum_of_elements(arr, n); # This code is contributed# by Akanksha Rai
// C# program to count pairs// whose sum divisible by 'K'using System; class GFG{    public static void sum_of_elements(int []arr,                                       int n)    {             int sumfirst = 0, sumsecond = 0;     for (int i = 0; i < n; i++)    {                 // Add elements in first half sum        if (i < n / 2)        {            sumfirst += arr[i];        }                 // Add elements in the second half sum        else        {            sumsecond += arr[i];        }    }     Console.WriteLine("Sum of first half elements is " +                                              sumfirst);         Console.WriteLine("Sum of second half elements is " +                                              sumsecond);} // Driver codestatic public void Main (){    int []arr = { 20, 30, 60, 10, 25, 15, 40 };    int n = arr.Length;         // Function call    sum_of_elements(arr, n);}} // This code is contributed by nidhiva
<script> // Javascript program to count pairs// whose sum divisible by 'K'     function sum_of_elements(arr , n)    {        var sumfirst = 0, sumsecond = 0;         for (i = 0; i < n; i++) {             // Add elements in first half sum            if (i < parseInt(n / 2))            {                sumfirst += arr[i];            }             // Add elements in the second half sum            else {                sumsecond += arr[i];            }        }         document.write(     "Sum of first half elements is " + sumfirst+"<br/>"        );         document.write(    "Sum of second half elements is " + sumsecond+"<br/>"        );    }     // Driver code             var arr = [ 20, 30, 60, 10, 25, 15, 40 ];        var n = arr.length;         // Function call        sum_of_elements(arr, n); // This code contributed by umadevi9616 </script>
Sum of first half elements is 110
Sum of second half elements is 90
 
Time complexity: O(N), as we are using a loop to traverse the array.Auxiliary Space: O(1), as we are not using any extra space.
nidhiva
princi singh
Akanksha_Rai
subhammahato348
umadevi9616
anikakapoor
rohitsingh07052
school-programming
Arrays
Mathematical
Arrays
Mathematical
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