Most Frequent Words

Given an integer n and several paragraphs of text, your task is to identify the n most frequent words across all paragraphs. The words are compared in a case-insensitive manner and any punctuation should be ignored. In the case of ties, the words should be sorted in alphabetical order.

The input consists of an integer n that indicates how many words to output, followed by an integer m which indicates the number of paragraphs, and then m lines each containing a paragraph of text. The output should contain the n most frequent words separated by a single space.

Note: All punctuation characters are to be removed and all letters converted to lowercase before processing.

For example, if n = 3 and the paragraphs are:

Hello world! This is a test. Hello again.
Test the function. Make sure it works, as this is important.
Hello from the other side. Test case number three, hello.

Then the output should be: hello test is

inputFormat

The first line of input contains an integer n, which specifies the number of most frequent words to output. The second line contains an integer m, representing the number of paragraphs. This is followed by m lines, each containing a paragraph of text.

Input format:

 n
 m
 paragraph_1
 paragraph_2
 ...
 paragraph_m

outputFormat

Output the n most frequent words separated by a single space in one line. The words should be in descending order of frequency. In case of ties, they are sorted in alphabetical order.

## sample

3
3
Hello world! This is a test. Hello again.
Test the function. Make sure it works, as this is important.
Hello from the other side. Test case number three, hello.

hello test is