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You have upcoming interviews and have selected specific chapters from BCtCI to read beforehand. Given an array, page_counts, where each element represents a chapter's page count, and the number of days, days, until your interview, determine the minimum number of pages you must read daily to finish on time. Assume that:

You must read all the pages of a chapter before moving on to another one.
If you finish a chapter on a given day, you practice for the rest of the day and don't start the next chapter until the next day.
len(page_counts) <= days.

Example:

Input: page_counts = [20, 15, 17, 10], days = 14
Output: 5

1def minPagesPerDay(page_counts: List[int], days: int) -> int:

2 def canFinish(speed):

3 d = 0

4 for pages in page_counts:

5 d += math.ceil(pages / speed)

6 return d <= days

8 l, r = 1, max(page_counts)

9 while l < r:

10 mid = (l + r) // 2

11 if canFinish(mid):

12 r = mid

13 else:

14 l = mid + 1

15 return l

Min Pages Per Day

Reference solution