875. Koko Eating Bananas

875. Koko Eating Bananas

class Solution:    
    def minEatingSpeed(self, piles: List[int], h: int) -> int:        
        left = 1
        right = max(piles)

        def helper(k: int) -> int:
            hours = 0
            for pile in piles:
                hours += pile // k
                if pile % k > 0:
                    hours += 1
            return hours

        while left < right:
            k = left + (right - left) // 2
            if helper(k) <= h:
                right = k
            else:
                left = k + 1

        return left