To compare 2 list and get the not matching items in a list-CodePudding

I have a 2 lists and the input looks like list1=["car", "boat", "sun", "ride"] and list2=["car_1", "car_2", sun_3"]. My expected output should be like output=["boat", "ride"]. My code snippet for your reference:

For i in list1:
   If any( i in e for e in list2):
      Print (i)

My code is not looping through the list1. Please Correct me what i am missing.

CodePudding user response：

You can just use List-Comprehension, then check for partial string in each item of list2 for each value in list1:

output=[v for v in list1 if not any(v in x for x in list2)]
print(output)
['boat', 'ride']

CodePudding user response：

The logic in your code will work with one modification: insert not before any(). To construct a list output, replace the print() statement with output.append(i) where output is initialized before the loop as output = [].

There is an alternative approach that optimizes for a more restricted type of matching. Assuming list2 contains only strings of the form prefix '_' suffix where prefix and suffix do not contain _, and also assuming we are to keep items in list1 unless they exactly match a prefix found in list2, you can do it this way:

prefSet = {x.split('_')[0] for x in list2}
print( [x for x in list1 if x not in prefSet] )