Spell check
Every now and then, students studying English are required to submit an essay to their teacher.
Teachers can have different reactions. Some are impressed when students use words that haven't been covered in class, appreciating the student's initiative. Others, however, may become upset and give a failing grade to those who "show off" their knowledge by using unfamiliar words.
Unfortunately, your teacher belongs to the latter group. She insists on strict adherence to the vocabulary taught in class.
This time, you face a new challenge. The essay due tomorrow is a test essay, meaning you must use every word you've learned in class at least once.
Before submitting your essay, you need to ensure that every word in your essay appears in the dictionary, and every word from the dictionary is used in your essay.
Input
The first line of the input file contains two numbers N and M (1 ≤ N ≤ 1000, 1 ≤ M ≤ 10000).
The next N lines each contain one word from the dictionary. All words consist of lowercase Latin letters, with each word being at least one character long and no longer than 20 characters. There are no extra spaces before or after the words.
The following M lines contain the text of the essay. The text includes uppercase and lowercase Latin letters, spaces, and punctuation marks: periods (.), commas (,), colons (:), semicolons (;), dashes (-), apostrophes ('), quotation marks ("), exclamation marks (!), and question marks (?). The total length of the text does not exceed 10^4 characters.
In this task, words are case-insensitive.
Output
If the essay meets all the requirements, print Everything is going to be OK.
If there are words in the essay that are not found in the dictionary, print Some words from the text are unknown.
If all words from the text are in the dictionary, but some words from the dictionary are missing in the text, print The usage of the vocabulary is not perfect.