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MD ARIFUL HAQUE

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# 1863. Sum of All Subset XOR Totals

1863. Sum of All Subset XOR Totals

Easy

The XOR total of an array is defined as the bitwise `XOR` of all its elements, or `0` if the array is empty.

• For example, the XOR total of the array `[2,5,6]` is `2 XOR 5 XOR 6 = 1`.

Given an array `nums`, return the sum of all XOR totals for every subset of `nums`.

Note: Subsets with the same elements should be counted multiple times.

An array `a` is a subset of an array `b` if `a` can be obtained from `b` by deleting some (possibly zero) elements of `b`.

Example 1:

• Input: nums = [1,3]
• Output: 28
• Explanation: The 4 subsets of [1,3] are:
• The empty subset has an XOR total of 0.
• [1] has an XOR total of 1.
• [3] has an XOR total of 3.
• [1,3] has an XOR total of 1 XOR 3 = 2.

`0 + 1 + 3 + 2 = 6`

Example 2:

• Input:nums = [5,1,6]
• Output: 28
• Explanation: The 8 subsets of [5,1,6] are:
• The empty subset has an XOR total of 0.
• [5] has an XOR total of 5.
• [1] has an XOR total of 1.
• [6] has an XOR total of 6.
• [5,1] has an XOR total of 5 XOR 1 = 4.
• [5,6] has an XOR total of 5 XOR 6 = 3.
• [1,6] has an XOR total of 1 XOR 6 = 7.
• [5,1,6] has an XOR total of 5 XOR 1 XOR 6 = 2.

`0 + 5 + 1 + 6 + 4 + 3 + 7 + 2 = 28`

Example 3:

• Input: nums = [3,4,5,6,7,8]
• Output: 480
• Explanation: The sum of all XOR totals for every subset is 480.

Constraints:

• `1 <= nums.length <= 12`
• `1 <= nums[i] <= 20`

Solution:

``````class Solution {

/**
* @param Integer[] \$nums
* @return Integer
*/
function subsetXORSum(\$nums) {
return array_reduce(\$nums, function(\$carry, \$item) {
return \$carry | \$item;
}) << (count(\$nums) - 1);
}
}
``````