Package g2501_2600.s2588_count_the_number_of_beautiful_subarrays

Class Solution

java.lang.Object

g2501_2600.s2588_count_the_number_of_beautiful_subarrays.Solution

public class Solution
extends java.lang.Object

2588 - Count the Number of Beautiful Subarrays.

Medium

You are given a 0-indexed integer array nums. In one operation, you can:

• Choose two different indices i and j such that 0 <= i, j < nums.length.
• Choose a non-negative integer k such that the kth bit ( 0-indexed ) in the binary representation of nums[i] and nums[j] is 1.
• Subtract 2k from nums[i] and nums[j].

A subarray is beautiful if it is possible to make all of its elements equal to 0 after applying the above operation any number of times.

Return the number of beautiful subarrays in the array nums.

A subarray is a contiguous non-empty sequence of elements within an array.

Example 1:

Input: nums = [4,3,1,2,4]

Output: 2

Explanation: There are 2 beautiful subarrays in nums: [4,3,1,2,4] and [4,3,1,2,4].

• We can make all elements in the subarray [3,1,2] equal to 0 in the following way:
  • Choose [3, 1, 2] and k = 1. Subtract 2¹ from both numbers. The subarray becomes [1, 1, 0].
  • Choose [1, 1, 0] and k = 0. Subtract 2⁰ from both numbers. The subarray becomes [0, 0, 0].
• We can make all elements in the subarray [4,3,1,2,4] equal to 0 in the following way:
  • Choose [4, 3, 1, 2, 4] and k = 2. Subtract 2² from both numbers. The subarray becomes [0, 3, 1, 2, 0].
  • Choose [0, 3, 1, 2, 0] and k = 0. Subtract 2⁰ from both numbers. The subarray becomes [0, 2, 0, 2, 0].
  • Choose [0, 2, 0, 2, 0] and k = 1. Subtract 2¹ from both numbers. The subarray becomes [0, 0, 0, 0, 0].

Example 2:

Input: nums = [1,10,4]

Output: 0

Explanation: There are no beautiful subarrays in nums.

Constraints:

• 1 <= nums.length <= 105
• 0 <= nums[i] <= 106

Constructor Summary

Constructors

Constructor	Description
Solution()

Method Summary

Modifier and Type	Method	Description
long	beautifulSubarrays(int[] nums)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

Solution

public Solution()

Method Details

beautifulSubarrays

public long beautifulSubarrays(int[] nums)