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How to check if a list is a sublist of another list in Python

How to check if a list is a sublist of another list in Python.

Here's a step-by-step tutorial on how to check if a list is a sublist of another list in Python:

  1. Start by defining two lists: the main list and the potential sublist. For example:
   main_list = [1, 2, 3, 4, 5, 6, 7, 8, 9]
   sublist = [3, 4, 5]

  1. Next, write a function to check if the sublist is present in the main list. You can name the function is_sublist for clarity.

  2. Inside the is_sublist function, use a loop to iterate through the main_list. You can use the range function to define the range of indices to check. 

   def is_sublist(main_list, sublist):
       for i in range(len(main_list)):
           # code to be added in the next step
  1. Inside the loop, check if the sublist matches a section of the main list starting from the current index i. Use slicing to extract the sublist-like section to compare.
   def is_sublist(main_list, sublist):
       for i in range(len(main_list)):
           if main_list[i:i+len(sublist)] == sublist:
               return True
       return False

  1. If the sublist is found, return True from the function. If the loop completes without finding a match, return False to indicate that the sublist is not present in the main list.

  2. Finally, you can call the is_sublist function, passing the main list and the potential sublist as arguments, and store the result in a variable. You can then print the result to see if the sublist is present.

   main_list = [1, 2, 3, 4, 5, 6, 7, 8, 9]
   sublist = [3, 4, 5]
   
   is_sublist_result = is_sublist(main_list, sublist)
   print(is_sublist_result)

The output will be True if the sublist is present in the main list, and False if it is not.

That's it! You now have a step-by-step tutorial on how to check if a list is a sublist of another list in Python.