class Solution:
    def findMinArrowShots(self, points: List[List[int]]) -> int:
        if len(points) == 0:
            return 0
        points.sort(key = lambda a:a[1])
        arrows = 1
        curr = points[0]
        for balloon in points:
            if curr[1] < balloon[0]:
                curr = balloon
                arrows+=1
        return arrows