Python: List Manipulation

Every day, we face this; you just need to remember.

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1. GET
2. ADD
3. REMOVE

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GET

Get first value of list

countries = ['Java', 'C++', 'JavaScript', 'C#', 'Python']
print(countries[0])

# Java

Get last value of list

countries = ['Java', 'C++', 'JavaScript', 'C#', 'Python']
print(countries[-1])

# Python

Get the first 2 elements of the list

countries = ['Java', 'C++', 'JavaScript', 'C#', 'Python']
print(countries[0:2])

# ['Java', 'C++']

Get the last 2 elements of the list

countries = ['Java', 'C++', 'JavaScript', 'C#', 'Python']
print(countries[-2:])

# ['C#', 'Python']

Get every second element of the list

countries = ['Java', 'C++', 'JavaScript', 'C#', 'Python']
print(countries[::2])

# ['Java', 'JavaScript', 'Python']

Get reverse list

countries = ['Java', 'C++', 'JavaScript', 'C#', 'Python']

countries.reverse()
print(countries)
# or
print(countries[::-1])

# ['Python', 'C#', 'JavaScript', 'C++', 'Java']

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ADD

Add an element to the beginning of the list

countries = ['Java', 'C++', 'JavaScript', 'C#', 'Python']
countries.insert(0, 'Go')
print(countries)

# ['Go', 'Java', 'C++', 'JavaScript', 'C#', 'Python']

Add an element to the end of the list

countries = ['Java', 'C++', 'JavaScript', 'C#', 'Python']
countries.append('Ruby')
print(countries)

# ['Java', 'C++', 'JavaScript', 'C#', 'Python', 'Ruby']

Add two elements to the list

countries = ['Java', 'C++', 'JavaScript', 'C#', 'Python']
countries.extend(['Go', 'Rust'])
print(countries)

# ['Java', 'C++', 'JavaScript', 'C#', 'Python', 'Go', 'Rust']

Append vs Extend

Note: append vs extend? Append - adds a list to a list. Extend - adds a list of values to a list.

Example:

countries = ['Java', 'C++', 'JavaScript', 'C#', 'Python']
countries.append(['Go', 'Rust'])
print(countries)

# ['Java', 'C++', 'JavaScript', 'C#', 'Python', ['Go', 'Rust']]

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REMOVE

Remove the last element of the list

countries = ['Java', 'C++', 'JavaScript', 'C#', 'Python']
countries.pop()
print(countries)

# ['Java', 'C++', 'JavaScript', 'C#']

Remove all occurrences of Python

countries = ['Java', 'C++', 'JavaScript', 'C#', 'Python']
countries.remove('Python')
print(countries)

# ['Java', 'C++', 'JavaScript', 'C#']

Remove the first element of the list

countries = ['Java', 'C++', 'JavaScript', 'C#', 'Python']
countries.pop(0)
print(countries)

# ['C++', 'JavaScript', 'C#', 'Python']

Remove the element at index 1

countries = ['Java', 'C++', 'JavaScript', 'C#', 'Python']
countries.pop(1)
print(countries)

#['Java', 'JavaScript', 'C#', 'Python']

Remove all elements from the list

countries = ['Java', 'C++', 'JavaScript', 'C#', 'Python']
countries.clear()
print(countries)

# []

If I have omitted something, please add your variants in the comments and I will incorporate them into the article. Thank you for your attention.