Python – Iterate through list without using the increment variable

Python Lists is much like flexible size arrays, declared in other languages like vector in C++, array list in Java, etc. Lists are heterogeneous, making it the most effective feature in Python. Lists are mutable, and hence can be modified even after they have been formed.

The most common approach is to iterate through a list using the increment variable i:

Python3

# Initializing the list
List = ["Geeks", 4, 'Geeks!']

# Using index variable to access
# each element of the list
for i in range(len(List)):
    print(List[i], end=" ")

Output:

Geeks 4 Geeks! 

This is the most common practice where index variable i is used for accessing each element of the list using only the index of that element in that list. However, there are various ways to iterate through a list without using the index variable.

Below are some methods to Iterate through a list without using the index variable:

Method 1: 

Explicitly iterating through the list using a common variable for each element rather than the index.

Python3

# Initializing the list
List = ["Geeks", 4, 'Geeks!']

# Using a common variable to access
# each element of the list
for ele in List:
    print(ele, end=" ")

Output:

Geeks 4 Geeks! 

Method 2: 

The enumerate() method adds a counter to the list and returns it in a form of enumerate object which can be used to access elements of the list 

Python3

# Initializing the list
List = ["Geeks", 4, 'Geeks!']

# Using enumerate()
for ele in enumerate(List):
    print(ele[1], end=" ")

Output:

Geeks 4 Geeks! 

Method 3: 

Using the nditer() method in numpy to iterate over a list after converting them into an array.

Python3

# Importing required modules
import numpy

# Initializing the list
List = ["Geeks", 4, 'Geeks!']

# Converting to array
Array = numpy.array(List)

# Using enumerate
for ele in numpy.nditer(Array):
    print(ele, end=" ")

Output:

Geeks 4 Geeks!