efficient substring match












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I have a list of unique string's(Approx 25,00,000) of different lengths and I am trying to find if there is any string which occurs as a substring of previous string.



here is my code



  def index_containing_substring(the_list, substring):
for i, s in enumerate(the_list):
if substring in s:
return i
return -1

def string_match():
test_list=['foo bar abc xml','fdff gdnfgf gdkgf','foo bar','abc','xml','xyz']
max_len=4 # I am storing the maximum length of sentence
# the list starts with reverse order
# i.e sentence with highest length are at the top
safe_to_add=
for s in test_list:
if len(s)==max_len:
safe_to_add.append(s)
else:
idx=index_containing_substring(safe_to_add,s)
if idx==-1:
safe_to_add.append(s)
else:
# process the substring
print('match found {} for {}'.format(test_list[idx],s))


This method works fine but I think it is pretty slow. Is there a better way to solve this problem.Using better Datastructure? using Trie or suffix tree?



Output
match found foo bar abc xml for foo bar
match found foo bar abc xml for abc
match found foo bar abc xml for xml








share









$endgroup$

















    0












    $begingroup$


    I have a list of unique string's(Approx 25,00,000) of different lengths and I am trying to find if there is any string which occurs as a substring of previous string.



    here is my code



      def index_containing_substring(the_list, substring):
    for i, s in enumerate(the_list):
    if substring in s:
    return i
    return -1

    def string_match():
    test_list=['foo bar abc xml','fdff gdnfgf gdkgf','foo bar','abc','xml','xyz']
    max_len=4 # I am storing the maximum length of sentence
    # the list starts with reverse order
    # i.e sentence with highest length are at the top
    safe_to_add=
    for s in test_list:
    if len(s)==max_len:
    safe_to_add.append(s)
    else:
    idx=index_containing_substring(safe_to_add,s)
    if idx==-1:
    safe_to_add.append(s)
    else:
    # process the substring
    print('match found {} for {}'.format(test_list[idx],s))


    This method works fine but I think it is pretty slow. Is there a better way to solve this problem.Using better Datastructure? using Trie or suffix tree?



    Output
    match found foo bar abc xml for foo bar
    match found foo bar abc xml for abc
    match found foo bar abc xml for xml








    share









    $endgroup$















      0












      0








      0





      $begingroup$


      I have a list of unique string's(Approx 25,00,000) of different lengths and I am trying to find if there is any string which occurs as a substring of previous string.



      here is my code



        def index_containing_substring(the_list, substring):
      for i, s in enumerate(the_list):
      if substring in s:
      return i
      return -1

      def string_match():
      test_list=['foo bar abc xml','fdff gdnfgf gdkgf','foo bar','abc','xml','xyz']
      max_len=4 # I am storing the maximum length of sentence
      # the list starts with reverse order
      # i.e sentence with highest length are at the top
      safe_to_add=
      for s in test_list:
      if len(s)==max_len:
      safe_to_add.append(s)
      else:
      idx=index_containing_substring(safe_to_add,s)
      if idx==-1:
      safe_to_add.append(s)
      else:
      # process the substring
      print('match found {} for {}'.format(test_list[idx],s))


      This method works fine but I think it is pretty slow. Is there a better way to solve this problem.Using better Datastructure? using Trie or suffix tree?



      Output
      match found foo bar abc xml for foo bar
      match found foo bar abc xml for abc
      match found foo bar abc xml for xml








      share









      $endgroup$




      I have a list of unique string's(Approx 25,00,000) of different lengths and I am trying to find if there is any string which occurs as a substring of previous string.



      here is my code



        def index_containing_substring(the_list, substring):
      for i, s in enumerate(the_list):
      if substring in s:
      return i
      return -1

      def string_match():
      test_list=['foo bar abc xml','fdff gdnfgf gdkgf','foo bar','abc','xml','xyz']
      max_len=4 # I am storing the maximum length of sentence
      # the list starts with reverse order
      # i.e sentence with highest length are at the top
      safe_to_add=
      for s in test_list:
      if len(s)==max_len:
      safe_to_add.append(s)
      else:
      idx=index_containing_substring(safe_to_add,s)
      if idx==-1:
      safe_to_add.append(s)
      else:
      # process the substring
      print('match found {} for {}'.format(test_list[idx],s))


      This method works fine but I think it is pretty slow. Is there a better way to solve this problem.Using better Datastructure? using Trie or suffix tree?



      Output
      match found foo bar abc xml for foo bar
      match found foo bar abc xml for abc
      match found foo bar abc xml for xml






      algorithm python-3.x strings





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      asked 7 mins ago









      RohitRohit

      54531020




      54531020






















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