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# Subtract String Lists in Python

• Last Updated : 01 Jul, 2020

Sometimes, while working with lists, we can have a problem in which we need to remove one list elements from other, i.e perform subtraction. This has application across many domains. Let’s discuss certain ways in which this task can be performed.

Method #1 : Using loop + `remove()`
The combination of above functionalities can be used to perform this task. In this, we perform the removal of elements using remove() and check for similar elements using loop.

 `# Python3 code to demonstrate working of``# Subtract String Lists``# using loop + remove()`` ` `# initialize lists``test_list1 ``=` `[``"gfg"``, ``"is"``, ``"best"``, ``"for"``, ``"CS"``]``test_list2 ``=` `[``"preffered"``, ``"is"``, ``"gfg"``]`` ` `# printing original lists``print``(``"The original list 1 : "` `+` `str``(test_list1))``print``(``"The original list 2 : "` `+` `str``(test_list2))`` ` `# Subtract String Lists``# using loop + remove()``res ``=` `[ ele ``for` `ele ``in` `test_list1 ]``for` `a ``in` `test_list2:``  ``if` `a ``in` `test_list1:``    ``res.remove(a)`` ` `# printing result``print``(``"The Subtracted list is : "` `+` `str``(res))`
Output :
```The original list 1 : ['gfg', 'is', 'best', 'for', 'CS']
The original list 2 : ['preffered', 'is', 'gfg']
The Subtracted list is : ['best', 'for', 'CS']
```

Method #2 : Using `Counter() + elements()`
The combination of above functions provide a shorthand to solve this problem. In this, we extract the count of elements in both list and then perform separation by their extraction using element().

 `# Python3 code to demonstrate working of``# Subtract String Lists``# using Counter() + elements()``from` `collections ``import` `Counter`` ` `# initialize lists``test_list1 ``=` `[``"gfg"``, ``"is"``, ``"best"``, ``"for"``, ``"CS"``]``test_list2 ``=` `[``"preffered"``, ``"is"``, ``"gfg"``]`` ` `# printing original lists``print``(``"The original list 1 : "` `+` `str``(test_list1))``print``(``"The original list 2 : "` `+` `str``(test_list2))`` ` `# Subtract String Lists``# using Counter() + elements()``res ``=` `list``((Counter(test_list1)``-``Counter(test_list2)).elements())`` ` `# printing result``print``(``"The Subtracted list is : "` `+` `str``(res))`
Output :
```The original list 1 : ['gfg', 'is', 'best', 'for', 'CS']
The original list 2 : ['preffered', 'is', 'gfg']
The Subtracted list is : ['best', 'for', 'CS']
```

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