- Difficulty: Hard
- Tags: LeetCode, Hard, Bit Manipulation, Array, Dynamic Programming, leetcode-1787, O(n + k * m), O(min(k * m, n))
Problem
You are given an array nums
and an integer k
. The XOR of a segment [left, right]
where left <= right
is the XOR
of all the elements with indices between left
and right
, inclusive: nums[left] XOR nums[left+1] XOR ... XOR nums[right]
.
Return the minimum number of elements to change in the array such that the XOR
of all segments of size k
is equal to zero.
Example 1:
Input: nums = [1,2,0,3,0], k = 1 Output: 3 Explanation: Modify the array from [1,2,0,3,0] to from [0,0,0,0,0].
Example 2:
Input: nums = [3,4,5,2,1,7,3,4,7], k = 3 Output: 3 Explanation: Modify the array from [3,4,5,2,1,7,3,4,7] to [3,4,7,3,4,7,3,4,7].
Example 3:
Input: nums = [1,2,4,1,2,5,1,2,6], k = 3 Output: 3 Explanation: Modify the array from [1,2,4,1,2,5,1,2,6] to [1,2,3,1,2,3,1,2,3].
Constraints:
1 <= k <= nums.length <= 2000
0 <= nums[i] < 210