Find the minimum value to be added so that array becomes balanced

12 Jul, 2022
Given an array of even size, task is to find minimum value that can be added to an element so that array become balanced. An array is balanced if the sum of the left half of the array elements is equal to the sum of right half. Suppose, we have an array 1 3 1 2 4 3. The Sum of first three elements is 1 + 3 + 1 = 5 and sum of last three elements is 2 + 4 + 3 = 9 So this is unbalanced, to make it balanced the minimum number we can add is 4 to any element in first half.
Examples : 
Chapters
descriptions off, selected
captions settings, opens captions settings dialog
captions off, selected
English
This is a modal window.
Beginning of dialog window. Escape will cancel and close the window.
End of dialog window.
Input : 1 2 1 2 1 3
Output : 2
Sum of first 3 elements is 1 + 2 + 1 = 4, 
sum of last three elements is 2 + 1 + 3 = 6
To make the array balanced you can add 2.

Input : 20 10
Output : 10
The idea is simple, we compute sums of first and second halves. Once these sums are computed, we return absolute difference of these two values. 
Implementation:
C++
Java
Python3
C#
PHP
Javascript
#include <bits/stdc++.h>using namespace std; // Returns minimum value that need to be added// to make array balanced.int minValueToBalance(int a[], int n){    // Calculating sum of first half elements    // of an array    int sum1 = 0;    for (int i = 0; i < n/2; i++)        sum1 += a[i];     // Calculating sum of other half elements    // of an array    int sum2 = 0;    for (int i = n/2; i < n; i++)        sum2 += a[i];     // calculating difference    return abs(sum1 - sum2);} // Driver codeint main(){    int arr[] = {1, 7, 1, 1, 3, 1};    int n = sizeof(arr)/sizeof(arr[0]);    cout << minValueToBalance(arr, n)<<endl;    return 0;}
// Java program to Find the minimum value// to be added so that array becomes balanced class Minimum{    // Returns minimum value that need to    // be added to make array balanced.    public static int minValueToBalance(int a[],                                        int n)    {        // Calculating sum of first half        // elements of an array        int sum1 = 0;        for (int i = 0; i < n / 2; i++)            sum1 += a[i];         // Calculating sum of other half        // elements of an array        int sum2 = 0;        for (int i = n/2; i < n; i++)            sum2 += a[i];         // calculating difference        return Math.abs(sum1 - sum2);    }         // driver code    public static void main(String[] args)    {        int arr[] = {1, 7, 1, 1, 3, 1};        int n = 6;        System.out.print(minValueToBalance(arr, n));    }} // This code is contributed by rishabh_jain
# Python3 program to Find the# minimum value to be added so that# array becomes balanced # Returns minimum value that need to# be added to make array balanced.def minValueToBalance(a, n):         # Calculating sum of first    # half elements of an array    sum1 = 0    for i in range( int(n / 2)):        sum1 += a[i]             # Calculating sum of other    # half elements of an array    sum2 = 0;    i = int(n / 2)    while i < n:        sum2 += a[i]        i = i + 1         # calculating difference    return abs(sum1 - sum2) # Driver codearr = [1, 7, 1, 1, 3, 1]n = len(arr)print(minValueToBalance(arr, n)) # This code is contributed by "Sharad_Bhardwaj".
// C# program to Find the minimum value// to be added so that array becomes balancedusing System; class Minimum {         // Returns minimum value that need to    // be added to make array balanced.    public static int minValueToBalance(int []a,                                        int n)    {                 // Calculating sum of first half        // elements of an array        int sum1 = 0;        for (int i = 0; i < n / 2; i++)            sum1 += a[i];         // Calculating sum of other half        // elements of an array        int sum2 = 0;        for (int i = n / 2; i < n; i++)            sum2 += a[i];         // calculating difference        return Math.Abs(sum1 - sum2);    }         // Driver Code    public static void Main()    {        int []arr = {1, 7, 1, 1, 3, 1};        int n = 6;        Console.Write(minValueToBalance(arr, n));    }} // This code is contributed by Nitin Mittal.
<?php// Returns minimum value// that need to be added// to make array balanced.function minValueToBalance($a, $n){    // Calculating sum of first    // half elements of an array    $sum1 = 0;    for ($i = 0; $i < $n / 2; $i++)        $sum1 += $a[$i];     // Calculating sum of other    // half elements of an array    $sum2 = 0;    for ( $i = $n / 2; $i < $n; $i++)        $sum2 += $a[$i];     // calculating difference    return abs($sum1 - $sum2);} // Driver code$arr = array(1, 7, 1, 1, 3, 1);$n = sizeof($arr) / sizeof($arr[0]);echo minValueToBalance($arr, $n); // This code is contributed// by nitin mittal.?>
<script> // Returns minimum value that need to be added// to make array balanced.function minValueToBalance(a, n){    // Calculating sum of first half elements    // of an array    let sum1 = 0;    for (let i = 0; i < Math.floor(n/2); i++)        sum1 += a[i];     // Calculating sum of other half elements    // of an array    let sum2 = 0;    for (let i = Math.floor(n/2); i < n; i++)        sum2 += a[i];     // calculating difference    return Math.abs(sum1 - sum2);} // Driver code    let arr = [1, 7, 1, 1, 3, 1];    let n = arr.length;    document.write(minValueToBalance(arr, n) + "<br>"); // This code is contributed by Surbhi Tyagi. </script>
4
Find the minimum value to be added so that array becomes balanced | GeeksforGeeks - YouTubeGeeksforGeeks532K subscribersFind the minimum value to be added so that array becomes balanced | GeeksforGeeksWatch laterShareCopy linkInfoShoppingTap to unmuteIf playback doesn't begin shortly, try restarting your device.You're signed outVideos you watch may be added to the TV's watch history and influence TV recommendations. To avoid this, cancel and sign in to YouTube on your computer.CancelConfirmMore videosMore videosSwitch cameraShareInclude playlistAn error occurred while retrieving sharing information. Please try again later.Watch on0:000:000:00 / 2:33•Live•<div class="player-unavailable"><h1 class="message">An error occurred.</h1><div class="submessage"><a href="https://www.youtube.com/watch?v=Zq1XLf5DTSo" target="_blank">Try watching this video on www.youtube.com</a>, or enable JavaScript if it is disabled in your browser.</div></div>
This article is contributed by Sahil Rajput. If you like GeeksforGeeks and would like to contribute, you can also write an article using write.geeksforgeeks.org or mail your article to review-team@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks. 
nitin mittal
surbhityagi15
hardikkoriintern
Arrays
Arrays
Writing code in comment?
Please use ide.geeksforgeeks.org,
generate link and share the link here.