palingrams.py

"""Finds word pairs that form palindromes from a dictionary file."""

import cProfile
import time


def load_file(file_name: str) -> list:
    """
    Load a text file and return a list of lowercase, stripped strings.

    Args:
        file_name (str): The path to the dictionary file.

    Returns:
        list: A list of words from the file.
    """
    with open(file_name, "r", encoding="utf-8") as file:
        content = file.read().split("\n")
        content = [x.lower().strip() for x in content]
        return content


def find_palingrams(dict_path: str) -> list:
    """
    Find all palingram pairs in a given dictionary file.

    Args:
        dict_path (str): The path to the dictionary file.

    Returns:
        list: A list of tuples containing the palingram pairs.
    """
    content = set(load_file(dict_path))
    palindromes = set()
    for w in content:
        for i in range(len(w)):
            prefix = w[:i]
            suffix = w[i:]
            if prefix == prefix[::-1] and suffix[::-1] in content and suffix[::-1] != w:
                palindromes.add((suffix[::-1], w))
            if suffix == suffix[::-1] and prefix[::-1] in content and prefix[::-1] != w:
                palindromes.add((w, prefix[::-1]))
    return palindromes


if __name__ == "__main__":
    start_time = time.time()
    palingrams = find_palingrams("dict.txt")
    end_time = time.time()

    print(f"\nRuntime for this program was {end_time - start_time:.4f} seconds.\n")
    sorted_palingrams = sorted(palingrams)
    print(f"Found {len(sorted_palingrams)} palingrams.")

    cProfile.run('find_palingrams("dict.txt")')