Maximum Number of Balls in a Box

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class Solution:
    def countBalls(self, lowLimit: int, highLimit: int) -> int:
        box_counts = {}

        # generate all the balls
        balls = list(range(lowLimit, highLimit+1))

        # for each ball
        for ball in balls:
            # convert the ball number into a string
            str_ball = str(ball)

            # initialize the box number to 0
            box = 0

            # for each digit in the string representation of the ball number
            for digit in str_ball:
                # add the digit (converted back to an integer) to the box number
                box += int(digit)

            # if this box already has some balls
            if box in box_counts:
                # increment the count of balls in this box
                box_counts[box] += 1
            else:
                # this box is encountered the first time, so initialize the count of balls in it to 1
                box_counts[box] = 1

        # after all balls have been put in their boxes, find the box with the maximum number of balls
        max_balls = max(box_counts.values())

        return max_balls

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class Solution:
    def countBalls(self, lowLimit: int, highLimit: int) -> int:
        cnt = [0] * 46
        for i in range(lowLimit, highLimit + 1):
            n = i
            _sum = 0
            while n > 0:
                _sum += n % 10
                n //= 10
            cnt[_sum] += 1
        return max(cnt)