3097-shortest-subarray-with-or-at-least-k-ii.rb

# frozen_string_literal: true

# 3097. Shortest Subarray With OR at Least K II
# https://leetcode.com/problems/shortest-subarray-with-or-at-least-k-ii
# Medium

=begin
You are given an array nums of non-negative integers and an integer k.
An array is called special if the bitwise OR of all of its elements is at least k.
Return the length of the shortest special non-empty subarray of nums, or return -1 if no special subarray exists.

Example 1:
Input: nums = [1,2,3], k = 2
Output: 1
Explanation:
The subarray [3] has OR value of 3. Hence, we return 1.
Example 2:
Input: nums = [2,1,8], k = 10
Output: 3
Explanation:
The subarray [2,1,8] has OR value of 11. Hence, we return 3.
Example 3:
Input: nums = [1,2], k = 0
Output: 1
Explanation:
The subarray [1] has OR value of 1. Hence, we return 1.

Constraints:
* 1 <= nums.length <= 2 * 105
* 0 <= nums[i] <= 109
* 0 <= k <= 109
=end

# @param {Integer[]} nums
# @param {Integer} k
# @return {Integer}
defminimum_subarray_length(nums,k)
or_val=0
ans=Float::INFINITY
bit_count=Array.new(32,0)
j=0

nums.each_with_indexdo |num,i|
or_val |= num
(0...32).eachdo |t|
bit_count[t] += (num & (1 << t)) != 0 ? 1 : 0
end

nextifor_val < k

whilej <= i && or_val >= k
(0...32).eachdo |t|
bit_count[t] += (nums[j] & (1 << t)) != 0 ? -1 : 0
or_val &= ~(1 << t)ifbit_count[t] == 0
end
ans=[ans,i - j + 1].min
j += 1
end
end

ans == Float::INFINITY ? -1 : ans
end

# **************** #
# TEST #
# **************** #

require"test/unit"
classTest_minimum_subarray_length < Test::Unit::TestCase
deftest_
assert_equal1,minimum_subarray_length([1,2,3],2)
assert_equal3,minimum_subarray_length([2,1,8],10)
assert_equal1,minimum_subarray_length([1,2],0)
end
end