20 lines
615 B
Python
20 lines
615 B
Python
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def invert(lst):
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lst = list(lst) # Makes sure arugment is a list
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#list_range = range(0, len(lst)) # Code I might have used if I used a dictionary comprehension
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ret_dict = dict() # Create empty dict
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counter = 0 # Create counter
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for i in lst:
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ret_dict[i] = counter # Assign each element of list to
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# its postion in list
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counter = counter + 1 # Increment counter
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if (len(lst) > len(ret_dict)): # Check if the length of new dict is less than
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return None # input list, if so, there is duplicates so return none
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return ret_dict # Return created dictionary
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