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

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 :**

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.

## C++

`#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 code` `int` `main()` `{` ` ` `int` `arr[] = {1, 7, 1, 1, 3, 1};` ` ` `int` `n = ` `sizeof` `(arr)/` `sizeof` `(arr[0]);` ` ` `cout << minValueToBalance(arr, n)<<endl;` ` ` `return` `0;` `}` |

## Java

`// 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

`# 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 code` `arr ` `=` `[` `1` `, ` `7` `, ` `1` `, ` `1` `, ` `3` `, ` `1` `]` `n ` `=` `len` `(arr)` `print` `(minValueToBalance(arr, n))` `# This code is contributed by "Sharad_Bhardwaj".` |

## C#

`// C# program to Find the minimum value` `// to be added so that array becomes balanced` `using` `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

`<?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.` `?>` |

## Javascript

`<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>` |

**Output :**

4

This article is contributed by **Sahil Rajput**. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.

Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the **DSA Self Paced Course** at a student-friendly price and become industry ready. To complete your preparation from learning a language to DS Algo and many more, please refer **Complete Interview Preparation Course****.**

In case you wish to attend **live classes **with experts, please refer **DSA Live Classes for Working Professionals **and **Competitive Programming Live for Students**.