3737. Count Subarrays With Majority Element I
You are given an integer array nums and an integer target.
Return the number of subarrays of nums in which target is the majority element.
The majority element of a subarray is the element that appears strictly more than half of the times in that subarray.
Example 1:
Input: nums = [1,2,2,3], target = 2
Output: 5
Explanation:
Valid subarrays with target = 2 as the majority element:
nums[1..1] = [2]nums[2..2] = [2]nums[1..2] = [2,2]nums[0..2] = [1,2,2]nums[1..3] = [2,2,3]
So there are 5 such subarrays.
Example 2:
Input: nums = [1,1,1,1], target = 1
Output: 10
Explanation:
All 10 subarrays have 1 as the majority element.
Example 3:
Input: nums = [1,2,3], target = 4
Output: 0
Explanation:
target = 4 does not appear in nums at all. Therefore, there cannot be any subarray where 4 is the majority element. Hence the answer is 0.
Constraints:
1 <= nums.length <= 10001 <= nums[i] <= 1091 <= target <= 109
ArrayHash TableDivide and ConquerSegment TreeMerge SortCountingPrefix Sum
Hints
Hint 1
Use brute force
Hint 2
Count all subarrays where
2 * count(target) > lengthPreparing judge…