915.partitionDisjoint.py

Question

Given an integer array nums, partition it into two (contiguous) subarrays left and right so that:

• Every element in left is less than or equal to every element in right.
• left and right are non-empty.
• left has the smallest possible size.

Return the length of left after such a partitioning.

Test cases are generated such that partitioning exists.

 

Example 1:

Input: nums = [5,0,3,8,6]
Output: 3
Explanation: left = [5,0,3], right = [8,6]

Example 2:

Input: nums = [1,1,1,0,6,12]
Output: 4
Explanation: left = [1,1,1,0], right = [6,12]

 

Constraints:

• 2 <= nums.length <= 105
• 0 <= nums[i] <= 106
• There is at least one valid answer for the given input.

Answer

• class Solution(object):
      def partitionDisjoint(self, nums):
          """
          :type nums: List[int]
          :rtype: int
          """
      l=0
      left_max=max_all=nums[0]
      n=len(nums)
      #print("n:",n)
      for i in range(1,n):
      #    print("i:",i)
          max_all=max(left_max,nums[i])
          if nums[i] <left_max:
              l = i
              left_max=max_all
      return l+1