Is Maximum Repeating Substring easy or hard?

Maximum Repeating Substring is classified as an Easy problem on LeetCode. The logic is straightforward once you recognize that the task is simply counting how many times a pattern can repeat while still appearing inside another string.

How to solve Maximum Repeating Substring in O(n)?

Strict O(n) solutions typically require specialized string matching techniques such as KMP-style pattern tracking or preprocessing repeated patterns. In most interview implementations, binary search combined with substring checks is considered efficient enough and simpler to implement.

Maximum Repeating Substring Python or Java solution?

Both Python and Java solutions typically construct repeated strings using multiplication or concatenation and check substring presence using built-in methods like 'in' in Python or 'contains' in Java. The same logic works across C++, JavaScript, and C# with similar string operations.

What is the best approach for Maximum Repeating Substring?

Binary search on the repetition count is the most efficient practical approach. Instead of checking every possible repetition, it searches the valid range of k and verifies whether word repeated k times appears in sequence. This reduces the number of substring checks and runs in about O(n log k) time.

Is Maximum Repeating Substring asked at Google/Amazon/Meta?

This problem reflects common string manipulation and pattern repetition questions frequently asked in interviews at large tech companies. Variants involving repeated patterns, substring search, and string matching appear in interview rounds at companies like Amazon, Google, and Meta.

What data structure is used in Maximum Repeating Substring?

The problem mainly uses basic string operations and substring matching. Some optimized reasoning uses binary search over integers representing repetition counts. No complex data structures are required beyond standard string handling.

What is the time complexity of Maximum Repeating Substring?

The brute force method checks each repetition sequentially and performs substring searches, leading to roughly O(n * m * k) time in the worst case. The optimized binary search approach reduces the checks to logarithmic steps, giving around O(n log k) time with constant extra space.

Description Hints 2 Solution Video 3:25

1668. Maximum Repeating Substring

Easy42.5% acceptance6 companies

For a string sequence, a string word is k-repeating if word concatenated k times is a substring of sequence. The word's maximum k-repeating value is the highest value k where word is k-repeating in sequence. If word is not a substring of sequence, word's maximum k-repeating value is 0.

Given strings sequence and word, return the maximum k-repeating value of word in sequence.

Example 1:

Input: sequence = "ababc", word = "ab"
Output: 2
Explanation: "abab" is a substring in "ababc".

Example 2:

Input: sequence = "ababc", word = "ba"
Output: 1
Explanation: "ba" is a substring in "ababc". "baba" is not a substring in "ababc".

Example 3:

Input: sequence = "ababc", word = "ac"
Output: 0
Explanation: "ac" is not a substring in "ababc".

Constraints:

1 <= sequence.length <= 100
1 <= word.length <= 100
sequence and word contains only lowercase English letters.

Asked at 6 companies

Pure Storage Asana Turing

Google Amazon Bloomberg

Topics

Hints open one at a time

Hint 1

The constraints are low enough for a brute force approach.

Hint 2

Try every k value from 0 upwards until word is no longer k-repeating.

3:25

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