1642. Furthest Building You Can Reach

https://leetcode.com/problems/furthest-building-you-can-reach/

Python

import heapq


class Solution:
    def furthestBuilding(self, heights: List[int], bricks: int, ladders: int) -> int:
        heap = []
        heapq.heapify(heap)

        for i in range(1, len(heights)):
            diff = heights[i] - heights[i-1]

            # Jump down, won't need bricks or ladders
            if diff <= 0:
                continue

            heapq.heappush(heap, diff)
            if len(heap) <= ladders:
                # Ladders still enough
                continue

            # Use the bricks on the miniumn cost of diff
            bricks -= heapq.heappop(heap)

            # Running out of bricks, reach the farest building
            if bricks < 0:
                return i-1

        # Resource is enough to reaching the end
        return len(heights)-1