Find a secret word using match feedback

Problem Statement

You are given a list of unique words of equal length, wordlist, along with an interactive oracle object master of type Mastermind.

One word from wordlist is designated as the secret. The oracle provides a single method:

• master.guess(word: str) -> int: Returns the number of exact matches (same character at the same position) between word and the secret. If word is not in wordlist, it returns -1.

Your task is to find and return the secret word using at most 10 calls to master.guess. If your strategy exhausts the query limit without identifying the secret, the test fails.

Function Interface

class Mastermind:
    def guess(self, word: str) -> int:
        pass

def find_secret_word(wordlist: list[str], master: Mastermind) -> str:
    pass

Inputs and Outputs

• wordlist: A list of strings where each string has length 6 consisting of lowercase English letters.
• master: An instance of Mastermind initialized with secret.
• Returns: The secret word as a string.

Constraints

• 2 <= len(wordlist) <= 100
• len(word) == 6 for all word in wordlist
• All words in wordlist are unique.
• secret is guaranteed to be in wordlist.
• You may call master.guess at most 10 times per test case.

Examples

Example 1

Input:
wordlist = ["acckzz", "ccbazz", "eiowzz", "abcczz"]
secret = "acckzz"

Execution:
master.guess("eiowzz") -> returns 2 (matches at positions 4 and 5: 'z', 'z')
Candidates remaining whose similarity to "eiowzz" is 2: ["acckzz", "ccbazz", "abcczz"]
master.guess("acckzz") -> returns 6

Output: "acckzz"
Explanation: "acckzz" matches all 6 characters of the secret.

Example 2

Input:
wordlist = ["hamlet", "kitten", "banner", "mantle"]
secret = "banner"

Execution:
master.guess("hamlet") -> returns 1 (matches 'a' at index 1)
Candidates filtered: only words with exactly 1 match to "hamlet" are retained.
master.guess("banner") -> returns 6

Output: "banner"

Edge Cases to Consider

• Zero matches: A score of 0 is informative; eliminate all candidates that share any characters at identical indices with the guessed word.
• Multiple disjoint clusters: When candidates have very low pairwise overlap, choosing an arbitrary candidate might yield zero matches repeatedly unless chosen strategically.
• Candidate elimination: When a guess returns k < 6, prune all words w in the remaining candidate pool where match(guess, w) != k.