File: maximum-repeating-substring/solution.py

Date: 2026-06-06

Time: 17:43

maximum-repeating-substring/solution.py

Purpose

This file implements LeetCode problem 1668 — Maximum Repeating Substring. It provides a single function that determines the highest value of k such that word repeated k times is a substring of sequence. It's one of ~500+ solution files in the leetcode-implementations repo, each owning exactly one problem's solution.

Key Components

longestAwesomeSubstring(sequence, word) -> int — The sole public function. Despite the misleading name (it has nothing to do with "awesome substrings"), it solves the maximum repeating substring problem.

Patterns

Linear search from below: The algorithm starts at k = 0 and increments, checking word * (k+1) in sequence at each step. This is a brute-force approach that leverages Python's built-in in operator for substring matching. The loop terminates at the first k where the next repetition isn't found, which is correct because if word * n isn't a substring, neither is word * (n+1).

Python string multiplication idiom: word * (k + 1) constructs the repeated string. This is idiomatic Python and avoids manual concatenation.

Dependencies

Imports: None — the solution is self-contained with no external dependencies.

Imported by: The testsolution.py files listed in the "Imported By" section are clearly an artifact of the repo's test infrastructure — those hundreds of test files don't actually import *this* solution. Only maximum-repeating-substring/testsolution.py meaningfully imports this function. The rest appear to be a bug in the dependency analysis tooling (likely every test file imports a common harness that transitively references all solutions, or the import graph was generated incorrectly).

Flow

1. Initialize k = 0.

2. Build the candidate string word * (k + 1).

3. Check if that candidate exists in sequence using Python's in operator (which uses a variant of Boyer-Moore/Horspool under the hood in CPython).

4. If found, increment k and repeat.

5. If not found, return k — the last successful repetition count.

Invariants

Error Handling

None. The function assumes valid string inputs per the LeetCode contract. Empty word would cause an infinite loop since "" in sequence is always True — but the problem constraints guarantee 1 <= len(word).

Naming Issue

The function is named longestAwesomeSubstring, which is the name for a different LeetCode problem (1542 — Find Longest Awesome Substring). The correct name for problem 1668 would be something like maxRepeating. This is likely a copy-paste error from the code generation pipeline.

Complexity

Topics to Explore

Beliefs