Watch 10 video solutions for Find the K-or of an Array, a easy level problem involving Array, Bit Manipulation. This walkthrough by NeetCode has 331,616 views views. Want to try solving it yourself? Practice on FleetCode or read the detailed text solution.
You are given an integer array nums, and an integer k. Let's introduce K-or operation by extending the standard bitwise OR. In K-or, a bit position in the result is set to 1 if at least k numbers in nums have a 1 in that position.
Return the K-or of nums.
Example 1:
Input: nums = [7,12,9,8,9,15], k = 4
Output: 9
Explanation:
Represent numbers in binary:
| Number | Bit 3 | Bit 2 | Bit 1 | Bit 0 |
|---|---|---|---|---|
| 7 | 0 | 1 | 1 | 1 |
| 12 | 1 | 1 | 0 | 0 |
| 9 | 1 | 0 | 0 | 1 |
| 8 | 1 | 0 | 0 | 0 |
| 9 | 1 | 0 | 0 | 1 |
| 15 | 1 | 1 | 1 | 1 |
| Result = 9 | 1 | 0 | 0 | 1 |
Bit 0 is set in 7, 9, 9, and 15. Bit 3 is set in 12, 9, 8, 9, and 15.
Only bits 0 and 3 qualify. The result is (1001)2 = 9.
Example 2:
Input: nums = [2,12,1,11,4,5], k = 6
Output: 0
Explanation: No bit appears as 1 in all six array numbers, as required for K-or with k = 6. Thus, the result is 0.
Example 3:
Input: nums = [10,8,5,9,11,6,8], k = 1
Output: 15
Explanation: Since k == 1, the 1-or of the array is equal to the bitwise OR of all its elements. Hence, the answer is 10 OR 8 OR 5 OR 9 OR 11 OR 6 OR 8 = 15.
Constraints:
1 <= nums.length <= 500 <= nums[i] < 2311 <= k <= nums.length