Program to find minimum space plane required for skydivers in k days in python

PythonServer Side ProgrammingProgramming

Suppose we have a list of numbers called nums where each value represents a group of people looking to skydive together. And we have another value k representing how many days they can apply for skydiving. We have to find the minimum capacity of the plane we need to be able to fulfill all requests within k days. The requests should be fulfilled in the order they were given and a plane can only fly once a day.

So, if the input is like nums = [16, 12, 18, 11, 13], k = 3, then the output will be 28, as 28-person airplane can group the given requests by [16, 12], [18], [11, 13].

To solve this, we will follow these steps −

  • if nums is empty, then
    • return 0
  • start := maximum of nums, end := sum of all elements of nums
  • while start < end, do
    • mid := (start + end) / 2
    • days := 1, temp := 0
    • for each num in nums, do
      • if temp + num > mid, then
        • days := days + 1
        • temp := num
      • otherwise,
        • temp := temp + num
    • if days > k, then
      • start := mid + 1
    • otherwise,
      • end := mid
  • return start

Let us see the following implementation to get better understanding −

Example 

Live Demo

class Solution:
   def solve(self, nums, k):
      if not nums:
         return 0

      start, end = max(nums), sum(nums)

      while start < end:
         mid = (start + end) // 2

         days = 1
         temp = 0
         for num in nums:
            if temp + num > mid:
               days += 1
               temp = num
            else:
               temp += num

         if days > k:
            start = mid + 1
         else:
            end = mid

      return start

ob = Solution()
nums = [16, 12, 18, 11, 13]
k = 3
print(ob.solve(nums, k))

Input

[16, 12, 18, 11, 13], 3

Output

28
raja
Published on 02-Dec-2020 09:22:52
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