reversed()

The reversed() function is a built-in function in Python that returns a reverse iterator for a sequence. It takes a sequence as an argument and returns an iterator that traverses the elements in the sequence in reverse order.

Parameter Values

Parameter Description
sequence

A sequence (e.g., a list, tuple, string, etc.) that you want to reverse.

Return Values

reversed() returns an iterator that accesses the given sequence in reverse.

How to Use reversed() in Python

Example 1:

The reversed() function returns an iterator that iterates over the elements of a sequence in reverse order.

nums = [1, 2, 3, 4, 5]
reversed_nums = reversed(nums)
for num in reversed_nums:
    print(num)
Example 2:

The reversed() function works with strings as well, iterating over characters in reverse order.

word = 'hello'
reversed_word = ''.join(reversed(word))
print(reversed_word)
Example 3:

The reversed() function can be used with custom classes that define the __reversed__ method to customize the reverse iteration behavior.

class CustomList:
    def __init__(self, data):
        self.data = data
    def __len__(self):
        return len(self.data)
    def __getitem__(self, index):
        return self.data[index]
    def __reversed__(self):
        return reversed(self.data)
custom_list = CustomList([1, 2, 3, 4, 5])
for num in reversed(custom_list):
    print(num)

Built-In Functions