Is Maximum Distance Between Unequal Words in Array I easy or hard?

Maximum Distance Between Unequal Words in Array I is categorized as an Easy problem. It mainly tests your ability to reason about array boundaries and reduce a brute-force O(n^2) search into an O(n) linear scan.

Maximum Distance Between Unequal Words in Array I Python/Java solution

The solution is identical across languages: check the first and last elements, then scan from both ends to locate the farthest different word. This approach can be implemented easily in Python, Java, C++, Go, or TypeScript using a single loop or two directional scans.

How to solve Maximum Distance Between Unequal Words in Array I in O(n)?

First compare the first and last words in the array. If they are different, return n-1. If they are equal, scan from the left to find the first word that differs from the first element and compute its distance from the end. Then scan from the right to find the first different word and compute its distance from the start. Return the larger of the two distances.

What is the best approach for Maximum Distance Between Unequal Words in Array I?

The best approach is a linear scan that compares the first and last elements of the array. If they differ, the maximum distance is n-1. If they are the same, scan from the left and right to find the farthest index with a different word. This solution runs in O(n) time with O(1) extra space.

Is Maximum Distance Between Unequal Words in Array I asked at Google/Amazon/Meta?

Problems based on array scanning and simple string comparisons are common in coding interviews at companies like Amazon, Google, and Meta. While this exact question may vary, the pattern of optimizing a brute-force pair search into an O(n) edge-based scan frequently appears in interview rounds.

What data structure is used in Maximum Distance Between Unequal Words in Array I?

The problem primarily uses a simple array (or list) of strings. No advanced data structures are required. The solution relies on index traversal and direct string comparison.

What is the time complexity of Maximum Distance Between Unequal Words in Array I?

The optimal solution runs in O(n) time because it scans the array at most once from each side. Space complexity is O(1) since only a few index variables are used and no additional data structures are required.

3696. Maximum Distance Between Unequal Words in Array I - Practice Online

You are given a string array words.

Find the maximum distance between two distinct indices i and j such that:

words[i] != words[j], and
the distance is defined as j - i + 1.

Return the maximum distance among all such pairs. If no valid pair exists, return 0.

Example 1:

Input: words = ["leetcode","leetcode","codeforces"]

Output: 3

Explanation:

In this example, words[0] and words[2] are not equal, and they have the maximum distance 2 - 0 + 1 = 3.

Example 2:

Input: words = ["a","b","c","a","a"]

Output: 4

Explanation:

In this example words[1] and words[4] have the largest distance of 4 - 1 + 1 = 4.

Example 3:

Input: words = ["z","z","z"]

Output: 0

Explanation:

In this example all the words are equal, thus the answer is 0.

Constraints:

1 <= words.length <= 100
1 <= words[i].length <= 10
words[i] consists of lowercase English letters.