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# How to iterate through a nested List in Python?

In this article, we are going to see how to iterate through a nested List. A list can be used to store multiple Data types such as Integers, Strings, Objects, and also another List within itself. This sub-list which is within the list is what is commonly known as the Nested List.

## Iterating through a Nested List

Lets us see how a typical nested list looks like :

There are multiple ways to iterate through a Nested List:

Method 1: Use of the index to iterate through the list

Use of Positive Index:

## Python3

 `# code``list` `=` `[``10``, ``20``, ``30``, ``40``, [``80``, ``60``, ``70``]]`` ` `# Printing sublist at index 4``print``(``list``[``4``])`` ` `# Printing 1st element of the sublist``print``(``list``[``4``][``0``])`` ` `# Printing 2nd element of the sublist``print``(``list``[``4``][``1``])`` ` `# Printing 3rd element of the sublist``print``(``list``[``4``][``2``])`

Output:

```[80, 60, 70]
80
60
70```

Use of Negative Index

## Python3

 `# code``list` `=` `[``10``, ``20``, ``30``, ``40``, [``80``, ``60``, ``70``]]`` ` `# Printing sublist at index 4``print``(``list``[``-``1``])`` ` `# Printing 1st element of the sublist``print``(``list``[``-``1``][``-``3``])`` ` `# Printing 2nd element of the sublist``print``(``list``[``-``1``][``-``2``])`` ` `# Printing 3rd element of the sublist``print``(``list``[``-``1``][``-``1``])`

Output:

```[80, 60, 70]
80
60
70```

Method 2: Use of loop to iterate through the list

## Python3

 `# code``# LIST``list` `=` `[[``"Rohan"``, ``60``], [``"Aviral"``, ``21``], ``        ``[``"Harsh"``, ``30``], [``"Rahul"``, ``40``],``        ``[``"Raj"``, ``20``]]`` ` `# looping through nested list using indexes``for` `names ``in` `list``:``    ``print``(names[``0``], ``"is"``, names[``1``],``          ``"years old."``)`

Output:

```Rohan is 60 years old.
Aviral is 21 years old.
Harsh is 30 years old.
Rahul is 40 years old.
Raj is 20 years old.```

Use of Temporary Variables inside a loop.

## Python3

 `# code``# LIST``list` `=` `[[``"Rohan"``, ``60``], [``"Aviral"``, ``21``], ``        ``[``"Harsh"``, ``30``], [``"Rahul"``, ``40``],``        ``[``"Raj"``, ``20``]]`` ` `# looping through nested list using multiple ``# temporary variables``for` `name, age ``in` `list``:``    ``print``(name, ``"is"``,``          ``age, ``"years old."``)`

Output:

```Rohan is 60 years old.
Aviral is 21 years old.
Harsh is 30 years old.
Rahul is 40 years old.
Raj is 20 years old.```

Method 3: Use of Slicing

## Python3

 `# code``# list``list` `=` `[``10``, ``20``, ``30``, ``40``,``        ``[``80``, ``60``, ``70``]]`` ` `# print the entire Sublist at index 4``print``(``list``[``4``][:])`` ` `# printing first two element``print``(``list``[``4``][``0` `: ``2``])`

Output:

```[80, 60, 70]
[80, 60]```