What is the time complexity of LeetCode 2369. Check if There is a Valid Partition For The Array?

The Python solution on this page runs in O(n).

What is the space complexity of LeetCode 2369. Check if There is a Valid Partition For The Array?

The Python solution on this page uses O(n) auxiliary space.

Check if There is a Valid Partition For The Array — LeetCode 2369 Python Solution

MediumArrayDynamic Programming

Problem: #2369
Pattern: Dynamic Programming
Reading time: 3 min
Source: leetcode.com

The problem

You are given a 0-indexed integer array nums. You have to partition the array into one or more contiguous subarrays.

Example

Input: nums = [4,4,4,5,6]
Output: true
Explanation: The array can be partitioned into the subarrays [4,4] and [4,5,6].

Python solution

Python

class Solution:
    def validPartition(self, nums: List[int]) -> bool:
        @cache
        def dfs(i: int) -> bool:
            if i >= n:
                return True
            a = i + 1 < n and nums[i] == nums[i + 1]
            b = i + 2 < n and nums[i] == nums[i + 1] == nums[i + 2]
            c = (
                i + 2 < n
                and nums[i + 1] - nums[i] == 1
                and nums[i + 2] - nums[i + 1] == 1
            )
            return (a and dfs(i + 2)) or ((b or c) and dfs(i + 3))

        n = len(nums)
        return dfs(0)

Complexity

Measure	Complexity
Time	O(n)
Space	O(n) auxiliary

Pattern: Dynamic Programming

Define a state, write the transition, and stop recomputing the same subproblem. LeetCode 2369. Check if There is a Valid Partition For The Array is filed here on both counts: the reference solution below belongs to the algorithm family this hub collects, and LeetCode tags it Dynamic Programming.

The dynamic programming guide has the Python template for the pattern and the 481 LeetCode problems that use it.

Frequently asked questions

How hard is LeetCode 2369. Check if There is a Valid Partition For The Array?: LeetCode 2369. Check if There is a Valid Partition For The Array is rated Medium on LeetCode.
What is the time complexity of LeetCode 2369. Check if There is a Valid Partition For The Array?: The Python solution on this page runs in O(n).
What is the space complexity of LeetCode 2369. Check if There is a Valid Partition For The Array?: The Python solution on this page uses O(n) auxiliary space.
What topics does LeetCode 2369. Check if There is a Valid Partition For The Array cover?: LeetCode 2369. Check if There is a Valid Partition For The Array is tagged Array and Dynamic Programming on LeetCode.