# Maximum possible difference of two subsets of an array

Last Updated : 24 Mar, 2023

Given an array of n-integers. The array may contain repetitive elements but the highest frequency of any element must not exceed two. You have to make two subsets such that the difference of the sum of their elements is maximum and both of them jointly contain all elements of the given array along with the most important condition, no subset should contain repetitive elements.

Examples:

```Input : arr[] = {5, 8, -1, 4}
Output : Maximum Difference = 18
Explanation :
Let Subset A = {5, 8, 4} & Subset B = {-1}
Sum of elements of subset A = 17, of subset B = -1
Difference of Sum of Both subsets = 17 - (-1) = 18

Input : arr[] = {5, 8, 5, 4}
Output : Maximum Difference = 12
Explanation :
Let Subset A = {5, 8, 4} & Subset B = {5}
Sum of elements of subset A = 17, of subset B = 5
Difference of Sum of Both subsets = 17 - 5 = 12```

Before solving this question we have to take care of some given conditions, and they are listed as:

• While building up the subsets, take care that no subset should contain repetitive elements. And for this, we can conclude that all such elements whose frequency are 2, going to be part of both subsets, and hence overall they don’t have any impact on the difference of subset-sum. So, we can easily ignore them.
• For making the difference of the sum of elements of both subset maximum we have to make subset in such a way that all positive elements belong to one subset and negative ones to other subsets.

Algorithm with time complexity O(n2):

```for i=0 to n-1
isSingleOccurrence = true;
for  j= i+1 to n-1

// if frequency of any element is two
// make both equal to zero
if arr[i] equals arr[j]
arr[i] = arr[j] = 0
isSingleOccurrence = false;
break;

if isSingleOccurrence == true
if (arr[i] > 0)
SubsetSum_1 += arr[i];
else
SubsetSum_2 += arr[i];
return abs(SubsetSum_1 - SubsetSum2)```

Implementation:

## C++

 `// CPP find maximum difference of subset sum ` `#include ` `using` `namespace` `std; ` ` `  `// function for maximum subset diff ` `int` `maxDiff(``int` `arr[], ``int` `n) ` `{ ` `    ``int` `SubsetSum_1 = 0, SubsetSum_2 = 0; ` `    ``for` `(``int` `i = 0; i <= n - 1; i++) { ` ` `  `        ``bool` `isSingleOccurrence = ``true``; ` `        ``for` `(``int` `j = i + 1; j <= n - 1; j++) { ` ` `  `            ``// if frequency of any element is two ` `            ``// make both equal to zero ` `            ``if` `(arr[i] == arr[j]) { ` `                ``isSingleOccurrence = ``false``; ` `                ``arr[i] = arr[j] = 0; ` `                ``break``; ` `            ``} ` `        ``} ` `        ``if` `(isSingleOccurrence) { ` `            ``if` `(arr[i] > 0) ` `                ``SubsetSum_1 += arr[i]; ` `            ``else` `                ``SubsetSum_2 += arr[i]; ` `        ``} ` `    ``} ` `    ``return` `abs``(SubsetSum_1 - SubsetSum_2); ` `} ` ` `  `// driver program ` `int` `main() ` `{ ` `    ``int` `arr[] = { 4, 2, -3, 3, -2, -2, 8 }; ` `    ``int` `n = ``sizeof``(arr) / ``sizeof``(arr[0]); ` `    ``cout << ``"Maximum Difference = "` `<< maxDiff(arr, n); ` `    ``return` `0; ` `} `

## Java

 `// java find maximum difference ` `// of subset sum ` `import` `java .io.*; ` ` `  `public` `class` `GFG { ` `     `  `    ``// function for maximum subset diff ` `    ``static` `int` `maxDiff(``int` `[]arr, ``int` `n) ` `    ``{ ` `        ``int` `SubsetSum_1 = ``0``, SubsetSum_2 = ``0``; ` `        ``for` `(``int` `i = ``0``; i <= n - ``1``; i++) ` `        ``{ ` `            ``boolean` `isSingleOccurrence = ``true``; ` `            ``for` `(``int` `j = i + ``1``; j <= n - ``1``; j++) ` `            ``{ ` `     `  `                ``// if frequency of any element ` `                ``// is two make both equal to ` `                ``// zero ` `                ``if` `(arr[i] == arr[j]) ` `                ``{ ` `                    ``isSingleOccurrence = ``false``; ` `                    ``arr[i] = arr[j] = ``0``; ` `                    ``break``; ` `                ``} ` `            ``} ` `            ``if` `(isSingleOccurrence) ` `            ``{ ` `                ``if` `(arr[i] > ``0``) ` `                    ``SubsetSum_1 += arr[i]; ` `                ``else` `                    ``SubsetSum_2 += arr[i]; ` `            ``} ` `        ``} ` `         `  `        ``return` `Math.abs(SubsetSum_1 - SubsetSum_2); ` `    ``} ` `     `  `    ``// driver program ` `    ``static` `public` `void` `main (String[] args) ` `    ``{ ` `        ``int` `[]arr = { ``4``, ``2``, -``3``, ``3``, -``2``, -``2``, ``8` `}; ` `        ``int` `n = arr.length; ` `         `  `        ``System.out.println(``"Maximum Difference = "` `                               ``+ maxDiff(arr, n)); ` `    ``} ` `} ` ` `  `// This code is contributed by vt_m. `

## Python3

 `# Python3 find maximum difference ` `# of subset sum ` ` `  `import` `math ` ` `  `# function for maximum subset diff ` `def` `maxDiff(arr, n) : ` `    ``SubsetSum_1 ``=` `0` `    ``SubsetSum_2 ``=` `0` `    ``for` `i ``in` `range``(``0``, n) : ` ` `  `        ``isSingleOccurrence ``=` `True` `        ``for` `j ``in` `range``(i ``+` `1``, n) : ` ` `  `            ``# if frequency of any element ` `            ``# is two make both equal to  ` `            ``# zero ` `            ``if` `(arr[i] ``=``=` `arr[j]) :  ` `                ``isSingleOccurrence ``=` `False` `                ``arr[i] ``=` `arr[j] ``=` `0` `                ``break` ` `  `        ``if` `(isSingleOccurrence ``=``=` `True``) : ` `            ``if` `(arr[i] > ``0``) : ` `                ``SubsetSum_1 ``+``=` `arr[i] ` `            ``else` `: ` `                ``SubsetSum_2 ``+``=` `arr[i] ` ` `  `    ``return` `abs``(SubsetSum_1 ``-` `SubsetSum_2) ` ` `  `# Driver Code ` `arr ``=` `[``4``, ``2``, ``-``3``, ``3``, ``-``2``, ``-``2``, ``8``] ` `n ``=` `len``(arr) ` `print` `(``"Maximum Difference = {}"` `               ``. ``format``(maxDiff(arr, n))) ` ` `  `# This code is contributed by Manish Shaw ` `# (manishshaw1) `

## C#

 `// C# find maximum difference of ` `// subset sum ` `using` `System; ` ` `  `public` `class` `GFG { ` `     `  `    ``// function for maximum subset diff ` `    ``static` `int` `maxDiff(``int` `[]arr, ``int` `n) ` `    ``{ ` `        ``int` `SubsetSum_1 = 0, SubsetSum_2 = 0; ` `        ``for` `(``int` `i = 0; i <= n - 1; i++) ` `        ``{ ` `     `  `            ``bool` `isSingleOccurrence = ``true``; ` `            ``for` `(``int` `j = i + 1; j <= n - 1; j++) ` `            ``{ ` `     `  `                ``// if frequency of any element ` `                ``// is two make both equal to ` `                ``// zero ` `                ``if` `(arr[i] == arr[j]) ` `                ``{ ` `                    ``isSingleOccurrence = ``false``; ` `                    ``arr[i] = arr[j] = 0; ` `                    ``break``; ` `                ``} ` `            ``} ` `            ``if` `(isSingleOccurrence) ` `            ``{ ` `                ``if` `(arr[i] > 0) ` `                    ``SubsetSum_1 += arr[i]; ` `                ``else` `                    ``SubsetSum_2 += arr[i]; ` `            ``} ` `        ``} ` `         `  `        ``return` `Math.Abs(SubsetSum_1 - SubsetSum_2); ` `    ``} ` `     `  `    ``// driver program ` `    ``static` `public` `void` `Main () ` `    ``{ ` `        ``int` `[]arr = { 4, 2, -3, 3, -2, -2, 8 }; ` `        ``int` `n = arr.Length; ` `         `  `        ``Console.WriteLine(``"Maximum Difference = "` `                              ``+ maxDiff(arr, n)); ` `    ``} ` `} ` ` `  `// This code is contributed by vt_m. `

## PHP

 ` 0) ` `                ``\$SubsetSum_1` `+= ``\$arr``[``\$i``]; ` `            ``else` `                ``\$SubsetSum_2` `+= ``\$arr``[``\$i``]; ` `        ``} ` `    ``} ` `    ``return` `abs``(``\$SubsetSum_1` `- ``\$SubsetSum_2``); ` `} ` ` `  `    ``// Driver Code ` `    ``\$arr` `= ``array``(4, 2, -3, 3, -2, -2, 8); ` `    ``\$n` `= sizeof(``\$arr``); ` `    ``echo` `"Maximum Difference = "` `, maxDiff(``\$arr``, ``\$n``); ` ` `  `// This code is contributed by nitin mittal ` `?> `

## Javascript

 ` `

Output

`Maximum Difference = 20`

Time Complexity O(n2)
Auxiliary Space: O(1)

Algorithm with time complexity O(n log n):

```-> sort the array
-> for i =0 to n-2
// consecutive two elements are not equal
// add absolute arr[i] to result
if arr[i] != arr[i+1]
result += abs(arr[i])
// else skip next element too
else
i++;

// special check for last two elements
-> if (arr[n-2] != arr[n-1])
result += arr[n-1]

-> return result;```

Implementation:

## C++

 `// CPP find maximum difference of subset sum ` `#include ` `using` `namespace` `std; ` ` `  `// function for maximum subset diff ` `int` `maxDiff(``int` `arr[], ``int` `n) ` `{ ` `    ``int` `result = 0; ` ` `  `    ``// sort the array ` `    ``sort(arr, arr + n); ` ` `  `    ``// calculate the result ` `    ``for` `(``int` `i = 0; i < n - 1; i++) { ` `        ``if` `(arr[i] != arr[i + 1]) ` `            ``result += ``abs``(arr[i]); ` `        ``else` `            ``i++; ` `    ``} ` ` `  `    ``// check for last element ` `    ``if` `(arr[n - 2] != arr[n - 1]) ` `        ``result += ``abs``(arr[n - 1]); ` ` `  `    ``// return result ` `    ``return` `result; ` `} ` ` `  `// driver program ` `int` `main() ` `{ ` `    ``int` `arr[] = { 4, 2, -3, 3, -2, -2, 8 }; ` `    ``int` `n = ``sizeof``(arr) / ``sizeof``(arr[0]); ` `    ``cout << ``"Maximum Difference = "` `<< maxDiff(arr, n); ` `    ``return` `0; ` `} `

## Java

 `// java find maximum difference of ` `// subset sum ` `import` `java. io.*; ` `import` `java .util.*; ` ` `  `public` `class` `GFG { ` ` `  `    ``// function for maximum subset diff ` `    ``static` `int` `maxDiff(``int` `[]arr, ``int` `n) ` `    ``{ ` `        ``int` `result = ``0``; ` `     `  `        ``// sort the array ` `        ``Arrays.sort(arr); ` `     `  `        ``// calculate the result ` `        ``for` `(``int` `i = ``0``; i < n - ``1``; i++) ` `        ``{ ` `            ``if` `(arr[i] != arr[i + ``1``]) ` `                ``result += Math.abs(arr[i]); ` `            ``else` `                ``i++; ` `        ``} ` `     `  `        ``// check for last element ` `        ``if` `(arr[n - ``2``] != arr[n - ``1``]) ` `            ``result += Math.abs(arr[n - ``1``]); ` `     `  `        ``// return result ` `        ``return` `result; ` `    ``} ` `     `  `    ``// driver program ` `    ``static` `public` `void` `main (String[] args) ` `    ``{ ` `        ``int``[] arr = { ``4``, ``2``, -``3``, ``3``, -``2``, -``2``, ``8` `}; ` `        ``int` `n = arr.length; ` `         `  `        ``System.out.println(``"Maximum Difference = "` `                                ``+ maxDiff(arr, n)); ` `    ``} ` `} ` ` `  `// This code is contributed by vt_m. `

## Python 3

 `# Python 3 find maximum difference  ` `# of subset sum ` ` `  `# function for maximum subset diff ` `def` `maxDiff(arr, n): ` ` `  `    ``result ``=` `0` ` `  `    ``# sort the array ` `    ``arr.sort() ` ` `  `    ``# calculate the result ` `    ``for` `i ``in` `range``(n ``-` `1``): ` `        ``if` `(``abs``(arr[i]) !``=` `abs``(arr[i ``+` `1``])): ` `            ``result ``+``=` `abs``(arr[i]) ` ` `  `        ``else``: ` `            ``pass` ` `  `    ``# check for last element ` `    ``if` `(arr[n ``-` `2``] !``=` `arr[n ``-` `1``]): ` `        ``result ``+``=` `abs``(arr[n ``-` `1``]) ` ` `  `    ``# return result ` `    ``return` `result ` ` `  `# Driver Code ` `if` `__name__ ``=``=` `"__main__"``: ` `     `  `    ``arr ``=` `[ ``4``, ``2``, ``-``3``, ``3``, ``-``2``, ``-``2``, ``8` `] ` `    ``n ``=` `len``(arr) ` `    ``print``(``"Maximum Difference = "` `, ` `                   ``maxDiff(arr, n)) ` ` `  `# This code is contributed by ita_c `

## C#

 `// C# find maximum difference ` `// of subset sum ` `using` `System; ` ` `  `public` `class` `GFG { ` ` `  `    ``// function for maximum subset diff ` `    ``static` `int` `maxDiff(``int` `[]arr, ``int` `n) ` `    ``{ ` `        ``int` `result = 0; ` `     `  `        ``// sort the array ` `        ``Array.Sort(arr); ` `     `  `        ``// calculate the result ` `        ``for` `(``int` `i = 0; i < n - 1; i++) ` `        ``{ ` `            ``if` `(arr[i] != arr[i + 1]) ` `                ``result += Math.Abs(arr[i]); ` `            ``else` `                ``i++; ` `        ``} ` `     `  `        ``// check for last element ` `        ``if` `(arr[n - 2] != arr[n - 1]) ` `            ``result += Math.Abs(arr[n - 1]); ` `     `  `        ``// return result ` `        ``return` `result; ` `    ``} ` `     `  `    ``// driver program ` `    ``static` `public` `void` `Main () ` `    ``{ ` `        ``int``[] arr = { 4, 2, -3, 3, -2, -2, 8 }; ` `        ``int` `n = arr.Length; ` `         `  `        ``Console.WriteLine(``"Maximum Difference = "` `                              ``+ maxDiff(arr, n)); ` `    ``} ` `} ` ` `  `// This code is contributed by vt_m. `

## PHP

 ` `

## Javascript

 ``

Output

`Maximum Difference = 20`

Time Complexity: O(n log n)
Auxiliary Space: O(1)

Algorithm with time complexity O(n):

```make hash table for positive elements:
for all positive elements(arr[i])
if frequency == 1
SubsetSum_1 += arr[i];
make hash table for negative elements:
for all negative elements
if frequency == 1
SubsetSum_2 += arr[i];
return abs(SubsetSum_1 - SubsetSum2)```

Implementation:

## C++

 `// CPP find maximum difference of subset sum ` `#include ` `using` `namespace` `std; ` ` `  `// function for maximum subset diff ` `int` `maxDiff(``int` `arr[], ``int` `n) ` `{ ` `    ``unordered_map<``int``, ``int``> hashPositive; ` `    ``unordered_map<``int``, ``int``> hashNegative; ` ` `  `    ``int` `SubsetSum_1 = 0, SubsetSum_2 = 0; ` ` `  `    ``// construct hash for positive elements ` `    ``for` `(``int` `i = 0; i <= n - 1; i++) ` `        ``if` `(arr[i] > 0) ` `            ``hashPositive[arr[i]]++; ` ` `  `    ``// calculate subset sum for positive elements ` `    ``for` `(``int` `i = 0; i <= n - 1; i++) ` `        ``if` `(arr[i] > 0 && hashPositive[arr[i]] == 1) ` `            ``SubsetSum_1 += arr[i]; ` ` `  `    ``// construct hash for negative elements ` `    ``for` `(``int` `i = 0; i <= n - 1; i++) ` `        ``if` `(arr[i] < 0) ` `            ``hashNegative[``abs``(arr[i])]++; ` ` `  `    ``// calculate subset sum for negative elements ` `    ``for` `(``int` `i = 0; i <= n - 1; i++) ` `        ``if` `(arr[i] < 0 &&  ` `            ``hashNegative[``abs``(arr[i])] == 1) ` `            ``SubsetSum_2 += arr[i]; ` ` `  `    ``return` `abs``(SubsetSum_1 - SubsetSum_2); ` `} ` ` `  `// driver program ` `int` `main() ` `{ ` `    ``int` `arr[] = { 4, 2, -3, 3, -2, -2, 8 }; ` `    ``int` `n = ``sizeof``(arr) / ``sizeof``(arr[0]); ` `    ``cout << ``"Maximum Difference = "` `<< maxDiff(arr, n); ` `    ``return` `0; ` `} `

## Java

 `// Java find maximum  ` `// difference of subset sum  ` `import` `java.util.*; ` `class` `GFG{ ` `   `  `// Function for maximum subset diff  ` `public` `static` `int` `maxDiff(``int` `arr[],  ` `                          ``int` `n)  ` `{  ` `  ``HashMap hashPositive = ``new` `HashMap<>(); ` `  ``HashMap hashNegative = ``new` `HashMap<>();  ` ` `  `  ``int` `SubsetSum_1 = ``0``,  ` `      ``SubsetSum_2 = ``0``;  ` ` `  `  ``// Construct hash for  ` `  ``// positive elements  ` `  ``for` `(``int` `i = ``0``; i <= n - ``1``; i++)  ` `  ``{ ` `    ``if` `(arr[i] > ``0``)  ` `    ``{ ` `      ``if``(hashPositive.containsKey(arr[i])) ` `      ``{ ` `        ``hashPositive.replace(arr[i],  ` `        ``hashPositive.get(arr[i]) + ``1``); ` `      ``} ` `      ``else` `      ``{ ` `        ``hashPositive.put(arr[i], ``1``); ` `      ``} ` `    ``} ` `  ``} ` ` `  `  ``// Calculate subset sum  ` `  ``// for positive elements  ` `  ``for` `(``int` `i = ``0``; i <= n - ``1``; i++)  ` `  ``{ ` `    ``if``(arr[i] > ``0` `&&  ` `       ``hashPositive.containsKey(arr[i])) ` `    ``{ ` `      ``if``(hashPositive.get(arr[i]) == ``1``) ` `      ``{ ` `        ``SubsetSum_1 += arr[i]; ` `      ``} ` `    ``} ` `  ``} ` ` `  `  ``// Construct hash for  ` `  ``// negative elements  ` `  ``for` `(``int` `i = ``0``; i <= n - ``1``; i++)  ` `  ``{ ` `    ``if` `(arr[i] < ``0``) ` `    ``{ ` `      ``if``(hashNegative.containsKey(Math.abs(arr[i]))) ` `      ``{ ` `        ``hashNegative.replace(Math.abs(arr[i]),  ` `        ``hashNegative.get(Math.abs(arr[i])) + ``1``); ` `      ``} ` `      ``else` `      ``{ ` `        ``hashNegative.put(Math.abs(arr[i]), ``1``); ` `      ``} ` `    ``} ` `  ``} ` ` `  `  ``// Calculate subset sum for ` `  ``// negative elements  ` `  ``for` `(``int` `i = ``0``; i <= n - ``1``; i++)  ` `  ``{ ` `    ``if` `(arr[i] < ``0` `&&  ` `        ``hashNegative.containsKey(Math.abs(arr[i]))) ` `    ``{ ` `      ``if``(hashNegative.get(Math.abs(arr[i])) == ``1``) ` `      ``{ ` `        ``SubsetSum_2 += arr[i];  ` `      ``} ` `    ``} ` `  ``} ` ` `  `  ``return` `Math.abs(SubsetSum_1 - SubsetSum_2);  ` `}  ` ` `  `// Driver code ` `public` `static` `void` `main(String[] args)  ` `{ ` `  ``int` `arr[] = {``4``, ``2``, -``3``, ``3``,  ` `               ``-``2``, -``2``, ``8``};  ` `  ``int` `n = arr.length; ` `  ``System.out.print(``"Maximum Difference = "` `+  ` `                    ``maxDiff(arr, n)); ` `} ` `} ` ` `  `// This code is contributed by divyeshrabadiya07`

## Python3

 `# Python3 find maximum difference of subset sum ` ` `  `# function for maximum subset diff ` `def` `maxDiff(arr, n): ` ` `  `    ``hashPositive ``=` `dict``() ` `    ``hashNegative ``=` `dict``() ` ` `  `    ``SubsetSum_1, SubsetSum_2 ``=` `0``, ``0` ` `  `    ``# construct hash for positive elements ` `    ``for` `i ``in` `range``(n): ` `        ``if` `(arr[i] > ``0``): ` `            ``hashPositive[arr[i]] ``=` `\ ` `                ``hashPositive.get(arr[i], ``0``) ``+` `1` ` `  `    ``# calculate subset sum for positive elements ` `    ``for` `i ``in` `range``(n): ` `        ``if` `(arr[i] > ``0` `and` `arr[i] ``in`  `            ``hashPositive.keys() ``and`  `            ``hashPositive[arr[i]] ``=``=` `1``): ` `            ``SubsetSum_1 ``+``=` `arr[i] ` ` `  `    ``# construct hash for negative elements ` `    ``for` `i ``in` `range``(n): ` `        ``if` `(arr[i] < ``0``): ` `            ``hashNegative[``abs``(arr[i])] ``=` `\ ` `                ``hashNegative.get(``abs``(arr[i]), ``0``) ``+` `1` ` `  `    ``# calculate subset sum for negative elements ` `    ``for` `i ``in` `range``(n): ` `        ``if` `(arr[i] < ``0` `and` `abs``(arr[i]) ``in`  `            ``hashNegative.keys() ``and`  `            ``hashNegative[``abs``(arr[i])] ``=``=` `1``): ` `            ``SubsetSum_2 ``+``=` `arr[i] ` ` `  `    ``return` `abs``(SubsetSum_1 ``-` `SubsetSum_2) ` ` `  `# Driver Code ` `arr ``=` `[``4``, ``2``, ``-``3``, ``3``, ``-``2``, ``-``2``, ``8``] ` `n ``=` `len``(arr) ` `print``(``"Maximum Difference ="``, maxDiff(arr, n)) ` ` `  `# This code is contributed by mohit kumar `

## C#

 `// C# find maximum  ` `// difference of subset sum  ` `using` `System; ` `using` `System.Collections.Generic; ` ` `  `class` `GFG { ` ` `  `    ``// Function for maximum subset diff  ` `    ``static` `int` `maxDiff(``int``[] arr, ``int` `n)  ` `    ``{  ` `      ``Dictionary<``int``, ``int``> hashPositive =  ` `        ``new` `Dictionary<``int``, ``int``>(); ` `      ``Dictionary<``int``, ``int``> hashNegative =  ` `        ``new` `Dictionary<``int``, ``int``>(); ` `      `  `      ``int` `SubsetSum_1 = 0, SubsetSum_2 = 0;  ` `      `  `      ``// Construct hash for  ` `      ``// positive elements  ` `      ``for` `(``int` `i = 0; i <= n - 1; i++)  ` `      ``{ ` `        ``if` `(arr[i] > 0)  ` `        ``{ ` `          ``if``(hashPositive.ContainsKey(arr[i])) ` `          ``{ ` `            ``hashPositive[arr[i]] += 1; ` `          ``} ` `          ``else` `          ``{ ` `            ``hashPositive.Add(arr[i], 1); ` `          ``} ` `        ``} ` `      ``} ` `      `  `      ``// Calculate subset sum  ` `      ``// for positive elements  ` `      ``for` `(``int` `i = 0; i <= n - 1; i++)  ` `      ``{ ` `        ``if``(arr[i] > 0 && hashPositive.ContainsKey(arr[i])) ` `        ``{ ` `          ``if``(hashPositive[arr[i]] == 1) ` `          ``{ ` `            ``SubsetSum_1 += arr[i]; ` `          ``} ` `        ``} ` `      ``} ` `      `  `      ``// Construct hash for  ` `      ``// negative elements  ` `      ``for` `(``int` `i = 0; i <= n - 1; i++)  ` `      ``{ ` `        ``if` `(arr[i] < 0) ` `        ``{ ` `          ``if``(hashNegative.ContainsKey(Math.Abs(arr[i]))) ` `          ``{ ` `            ``hashNegative[(Math.Abs(arr[i]))] += 1;  ` `          ``} ` `          ``else` `          ``{ ` `            ``hashNegative.Add(Math.Abs(arr[i]), 1); ` `          ``} ` `        ``} ` `      ``} ` `      `  `      ``// Calculate subset sum for ` `      ``// negative elements  ` `      ``for` `(``int` `i = 0; i <= n - 1; i++)  ` `      ``{ ` `        ``if` `(arr[i] < 0 &&  ` `            ``hashNegative.ContainsKey(Math.Abs(arr[i]))) ` `        ``{ ` `          ``if``(hashNegative[(Math.Abs(arr[i]))] == 1) ` `          ``{ ` `            ``SubsetSum_2 += arr[i];  ` `          ``} ` `        ``} ` `      ``} ` `      `  `      ``return` `Math.Abs(SubsetSum_1 - SubsetSum_2);  ` `    ``} ` `   `  `  ``// Driver code   ` `  ``static` `void` `Main() { ` `      ``int``[] arr = {4, 2, -3, 3, -2, -2, 8};  ` `      ``int` `n = arr.Length; ` `      ``Console.WriteLine(``"Maximum Difference = "` `+  ` `                        ``maxDiff(arr, n)); ` `  ``} ` `} ` ` `  `// This code is contributed by divesh072019`

## Javascript

 ``

Output

`Maximum Difference = 20`

Time Complexity: O(n)
Auxiliary Space: O(n)

Previous Article
Next Article
Article Tags :
Practice Tags :