hardArrayBinary Indexed TreeBinary Search 0 views

Find the Longest Valid Obstacle Course at Each Position

You want to build some obstacle courses.

You want to build some obstacle courses. You are given a 0-indexed integer array obstacles of length n, where obstacles[i] describes the height of the ith obstacle.

For every index i between 0 and n - 1 (inclusive), find the length of the longest obstacle course in obstacles such that:

Return an array ans of length n, where ans[i] is the length of the longest obstacle course for index i as described above.

Find the Longest Valid Obstacle Course at Each Position diagram

Example 1

Input: obstacles = [1,2,3,2]

Output: [1,2,3,3]

Explanation: The longest valid obstacle course at each position is: - i = 0: [1], [1] has length 1. - i = 1: [1,2], [1,2] has length 2. - i = 2: [1,2,3], [1,2,3] has length 3. - i = 3: [1,2,3,2], [1,2,2] has length 3.

Example 2

Input: obstacles = [2,2,1]

Output: [1,2,1]

Explanation: The longest valid obstacle course at each position is: - i = 0: [2], [2] has length 1. - i = 1: [2,2], [2,2] has length 2. - i = 2: [2,2,1], [1] has length 1.

Example 3

Input: obstacles = [3,1,5,6,4,2]

Output: [1,1,2,3,2,2]

Explanation: The longest valid obstacle course at each position is: - i = 0: [3], [3] has length 1. - i = 1: [3,1], [1] has length 1. - i = 2: [3,1,5], [3,5] has length 2. [1,5] is also valid. - i = 3: [3,1,5,6], [3,5,6] has length 3. [1,5,6] is also valid. - i = 4: [3,1,5,6,4], [3,4] has length 2. [1,4] is also valid. - i = 5: [3,1,5,6,4,2], [1,2] has length 2.

Constraints

  • n == obstacles.length
  • 1 <= n <= 10^5
  • 1 <= obstacles[i] <= 10^7

Hints

Companies

No companies reported yet.

Discussion

Sign in to join the discussion.

Loading discussion...

Test results

No test cases yet.