similarities less helpers.py, and index.html

helpers.py

from nltk.tokenize import sent_tokenize

def lines(a, b):
    """Return lines in both a and b"""
    (a, b) = (a.split('\n'), b.split('\n'))


    # TODO
    return [line for line in a if line in b]


def sentences(a, b):
    """Return sentences in both a and b"""
    (a, b) = (sent_tokenize(a), sent_tokenize(b))

    sentences = set([line for line in a if line in b])

    unique_list = list(sentences)

    # TODO
    return unique_list


def substrings(a, b, n):
    """Return substrings of length n in both a and b"""
    sub_list = []

    strlen = len(a)-1

    n = 2
    for i in range(0,strlen,n):
        substring = a[i:i+n]
        if substring in b and substring.isalpha():
    	    sub_list.append(substring)

    sub_list = set(sub_list)
    sub_list = list(sub_list)

    # TODO
    return sub_list

index.html

{% extends "layout.html" %}

{% block body %}

    <div class="col">
        <form action="/compare" enctype="multipart/form-data" method="post">

            <form action="/compare" enctype="multipart/form-data" method="post">
                        <input type="file" name="file1"><br><br>
                        <input type="file" name="file2"><br><br>
                        choose an algorithm:
						<select
						name="algorithm"
						onchange="if (this.value == 'substrings') {
							document.getElementById('length').style.display = 'block'
							'block'
							}else{document.getElementById('length').style.display = 'none'}
								">
                            <option selected="selected" value="lines">lines</option>
                            <option value="sentences">sentences</option>
                            <option value="substrings">substrings</option>
                        </select><br><br>
                        <p id="length" style="display: none;">
                        	<input
                        	placeholder="substring length"
                        	type="number"
                        	name="length">
                        </p>
                        <input type="submit" value="Submit">
                    </form>

        </form>
    </div>
    {# reload page on back button #}
    <script type="text/javascript">
    	window.addEventListener( "pageshow", function ( event ) {
    	  var historyTraversal = event.persisted ||
    	                         ( typeof window.performance != "undefined" &&
    	                              window.performance.navigation.type === 2 );
    	  if ( historyTraversal ) {
    	    // Handle page restore.
    	    window.location.reload();
    	  }
    	});
    </script>

{% endblock %}