OlympiadCode/leetcode_py/1944.py

from typing import List


# use monotonic stack
class Solution:
    def canSeePersonsCount(self, heights: List[int]) -> List[int]:
        n = len(heights)
        result = [0] * n
        stack = []
        # Process from right to left
        for i in range(n - 1, -1, -1):
            count = 0
            # Pop elements shorter than current height
            while stack and heights[stack[-1]] < heights[i]:
                count += 1
                stack.pop()

            # If stack not empty, can see one more person
            if stack:
                count += 1

            result[i] = count
            stack.append(i)

        return result