tasks/filesystem/standard/file_context/pattern_matching/description.md

Please use FileSystem tools to finish the following task:

Task Description

Your task is to find all files that contain a substring of 30 or more characters that also appears in large_file.txt. You are not allowed to use python code.

Task Objectives

1. Read the reference file large_file.txt to understand its content
2. Examine each file from file_01.txt to file_20.txt
3. Find files that contain a substring of 30 or more characters that matches a substring in large_file.txt
4. Create a file answer.txt and write the results to it with the following format:
   • One line per matching file
   • Format: filename.txt,start_position
   • Where start_position is the character position (1-indexed) of the matching substring in large_file.txt
   • Do not add any things else other than filename.txt,start_position.