Non-decreasing Array

Non-decreasing Array

Given an array with n integers, your task is to check if it could become non-decreasing by modifying at most 1 element.
We define an array is non-decreasing if array[i] <= array[i + 1] holds for every i (1 <= i < n).

Example

Input: [4,2,3]
Output: True
Explanation: You could modify the first 4 to 1 to get a non-decreasing array.

Solution

class Solution:
    def checkPossibility(self, nums: List[int]) -> bool:
        count = 0
        if len(nums)==1:
            return True
        for i in range(len(nums)-1):
            if nums[i]>nums[i+1]:
                count += 1
                if i == 0:
                    nums[i] = nums[i+1]
                elif nums[i-1]<=nums[i+1]:
                    nums[i] = nums[i-1]
                else:
                    nums[i+1] = nums[i]
            if count>1:
                return False
        return True