{"id":126564,"date":"2022-07-15T11:53:32","date_gmt":"2022-07-15T11:53:32","guid":{"rendered":"https:\/\/blog.finxter.com\/?p=473156"},"modified":"2022-07-15T11:53:32","modified_gmt":"2022-07-15T11:53:32","slug":"python-slice-remove-first-and-last-element-from-a-list","status":"publish","type":"post","link":"https:\/\/sickgaming.net\/blog\/2022\/07\/15\/python-slice-remove-first-and-last-element-from-a-list\/","title":{"rendered":"Python Slice Remove First and Last Element from a List"},"content":{"rendered":"\n
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5\/5 – (1 vote) <\/div>\n<\/div>\n

Problem Formulation<\/h2>\n

\"\ud83d\udcac\" Question<\/strong>: Given a Python list<\/a> stored in a variable lst<\/code>. How to remove the first and last elements from the list lst<\/code>?<\/p>\n

Example<\/strong>: The list ['Alice', 'Bob', 'Carl', 'Dave']<\/code> stored in variable lst<\/code> becomes ['Bob', 'Carl']<\/code>.<\/p>\n

Method 1: Slicing List[1:-1]<\/h2>\n

To remove the first and last elements from a Python list, use the expression lst = lst[1:-1]<\/code> that uses a Python feature called slicing<\/a> with the syntax variable[start:stop]<\/code> to iterate over a sequence starting from the start<\/code> index (included) and ending in the element at stop<\/code> index (excluded). If stop<\/code> is a negative integer such as -i<\/code>, Python takes the i-th right-most element. <\/p>\n

Here’s an example:<\/p>\n

lst = ['Alice', 'Bob', 'Carl', 'Dave']\nlst = lst[1:-1]\nprint(lst)\n# ['Bob', 'Carl']<\/pre>\n
This code snippet removes the first element 'Alice'<\/code> and the last element 'Dave'<\/code> from the list.<\/p>\n
Note that this approach also works for lists with one element:<\/p>\n
lst = ['Alice']\nlst = lst[1:-1]\nprint(lst)\n# []\n<\/pre>\n
… and also for an empty list<\/a> with zero elements:<\/p>\n
lst = []\nlst = lst[1:-1]\nprint(lst)\n# []\n<\/pre>\n
Feel free to get some background on slicing by watching the following tutorial:<\/p>\n
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