# Python : How to Insert an element at specific index in List ?

Lists are similar to dynamically sized arrays, which are declared in other languages(e.g., vector in C++ and ArrayList in Java). Lists do not have to be homogeneous all of the time, which makes it a very useful tool in Python. DataTypes such as Integers, Strings, and Objects can all be included in a single list. Lists are mutable, which means they can be changed after they’ve been created.

An index refers to a position within an list.

Given, a list the task is to insert an element at specific index in given list.

## Insert an element at Specific Index in List

### 1)Insert() function

Syntax:

givenlist.insert(index, element)

Parameters:

index - the position in the array at which the element must be inserted.
element - the element that will be added to the list.

Return:

This method does not return a value, but instead inserts the specified element at the specified index.

### 2)Inserting an element at a specific position

Suppose we want to insert ‘python’ in a givenlist at index 3 we can pass arguments like

insert(3,value) where value=‘python’

Below is the implementation:

# given list
givenlist = ['hello', 'this', 'is', 'BTechGeeks']
# given value
value = 'python'
# given index
index = 3
# inserting the given value at given index
givenlist.insert(index, value)
# print the list
print(givenlist)


Output:

['hello', 'this', 'is', 'python', 'BTechGeeks']

### 3)Inserting element at the first position of the list

We know that the starting index of list is 0 so we give 0 as index while inserting the given value.

Below is the implementation:

# given list
givenlist = ['hello', 'this', 'is', 'BTechGeeks']
# given value
value = 'python'
# inserting the given value at starting position
givenlist.insert(0, value)
# print the list
print(givenlist)


Output:

['python', 'hello', 'this', 'is', 'BTechGeeks']

### 4)Inserting element at the end position of the list

We know that the last index of the list is len(list)-1 to insert element at end we use len(list) as parameter.

Passing this index to insert function inserts the element at the end of the list.

Below is the implementation:

# given list
givenlist = ['hello', 'this', 'is', 'BTechGeeks']
# given value
value = 'python'
# inserting the given value at end position
givenlist.insert(len(givenlist), value)
# print the list
print(givenlist)


Output:

['hello', 'this', 'is', 'BTechGeeks', 'python']

### 5)Insert all elements of second list at specific index in given list

By slicing we can insert it easily .

Splice given list from 0 to index-1 and merge all of list2’s elements into it. Then, from index to the end of the list, merge all of the remaining elements.

Below is the implementation:

# given list
givenlist = ['hello', 'this', 'is', 'BTechGeeks']
# given value
givenlist2 = ['welcome', 'to', 'python']
# given index
index = 2
# inserting the given value using slicing
givenlist = givenlist[:index]+givenlist2+givenlist[index:]
# print the list
print(givenlist)


Output:

['hello', 'this', 'welcome', 'to', 'python', 'is', 'BTechGeeks']

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