Is Max Chunks To Make Sorted easy or hard?

Max Chunks To Make Sorted is categorized as a Medium problem. The implementation is simple once the greedy observation is discovered, but recognizing the correct chunk boundary condition requires algorithmic insight.

Max Chunks To Make Sorted Python/Java solution

In Python or Java, iterate through the array while updating a variable that stores the maximum value seen so far. Whenever this maximum equals the current index, increment a chunk counter. The implementation is short and runs in O(n) time with constant extra space.

How to solve Max Chunks To Make Sorted in O(n)?

Track the maximum element encountered while iterating through the array. If the maximum value equals the current index, all elements within that segment belong in the first i+1 positions of the sorted array. That position becomes a valid chunk boundary, and you increment the chunk count.

What is the best approach for Max Chunks To Make Sorted?

The best approach uses a greedy scan with maximum tracking. While iterating through the array, keep track of the maximum value seen so far. When the running maximum equals the current index, a valid chunk boundary exists. This method runs in O(n) time and O(1) space.

Is Max Chunks To Make Sorted asked at Google/Amazon/Meta?

Variants of this problem appear in interviews at companies like Amazon, Google, and other large tech firms because it tests greedy reasoning and array invariants. Interviewers often expect candidates to recognize the O(n) greedy boundary condition.

What data structure is used in Max Chunks To Make Sorted?

The most common solution only uses a running integer variable to track the maximum value, making it a greedy array traversal problem. Conceptually, related variants can be solved using a monotonic stack when duplicates or different constraints are introduced.

What is the time complexity of Max Chunks To Make Sorted?

The optimal greedy solution runs in O(n) time because the array is scanned once while maintaining a running maximum. A simpler approach that sorts a copy of the array requires O(n log n) time due to the sorting step.

Description Hints 1 Solution Video 10:50

769. Max Chunks To Make Sorted

Medium64.1% acceptance7 companies

You are given an integer array arr of length n that represents a permutation of the integers in the range [0, n - 1].

We split arr into some number of chunks (i.e., partitions), and individually sort each chunk. After concatenating them, the result should equal the sorted array.

Return the largest number of chunks we can make to sort the array.

Example 1:

Input: arr = [4,3,2,1,0]
Output: 1
Explanation:
Splitting into two or more chunks will not return the required result.
For example, splitting into [4, 3], [2, 1, 0] will result in [3, 4, 0, 1, 2], which isn't sorted.

Example 2:

Input: arr = [1,0,2,3,4]
Output: 4
Explanation:
We can split into two chunks, such as [1, 0], [2, 3, 4].
However, splitting into [1, 0], [2], [3], [4] is the highest number of chunks possible.

Constraints: