- Difficulty: Hard
- Tags: LeetCode, Hard, Binary Indexed Tree, Segment Tree, Queue, Array, Divide and Conquer, Dynamic Programming, Monotonic Queue, leetcode-2407, O(nlogn), O(n), Coordinate Compression
Problem
You are given an integer array nums
and an integer k
.
Find the longest subsequence of nums
that meets the following requirements:
- The subsequence is strictly increasing and
- The difference between adjacent elements in the subsequence is at most
k
.
Return the length of the longest subsequence that meets the requirements.
A subsequence is an array that can be derived from another array by deleting some or no elements without changing the order of the remaining elements.
Example 1:
Input: nums = [4,2,1,4,3,4,5,8,15], k = 3 Output: 5 Explanation: The longest subsequence that meets the requirements is [1,3,4,5,8]. The subsequence has a length of 5, so we return 5. Note that the subsequence [1,3,4,5,8,15] does not meet the requirements because 15 - 8 = 7 is larger than 3.
Example 2:
Input: nums = [7,4,5,1,8,12,4,7], k = 5 Output: 4 Explanation: The longest subsequence that meets the requirements is [4,5,8,12]. The subsequence has a length of 4, so we return 4.
Example 3:
Input: nums = [1,5], k = 1 Output: 1 Explanation: The longest subsequence that meets the requirements is [1]. The subsequence has a length of 1, so we return 1.
Constraints:
1 <= nums.length <= 105
1 <= nums[i], k <= 105