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Python: Insert an element in a given list after every nth position

Python List: Exercise - 170 with Solution

Write a Python program to insert an element in a given list after every nth position.

Sample Solution:

Python Code:

def insert_elemnt_nth(lst, ele, n):
    result = []
    for st_idx in range(0, len(lst), n):
        result.extend(lst[st_idx:st_idx+n])
        result.append(ele)
    result.pop()    
    return result

nums = [1,2,3,4,5,6,7,8,9,0]
print("Original list:")
print(nums)
i_ele = 'a'
i_ele_pos = 2
print("\nInsert",i_ele,"in the said list after",i_ele_pos,"nd element:")
print(insert_elemnt_nth(nums, i_ele, i_ele_pos))
i_ele = 'b'
i_ele_pos = 4
print("\nInsert",i_ele,"in the said list after",i_ele_pos,"th element:")
print(insert_elemnt_nth(nums, i_ele, i_ele_pos))

Sample Output:

Original list:
[1, 2, 3, 4, 5, 6, 7, 8, 9, 0]

Insert a in the said list after 2 nd element:
[1, 2, 'a', 3, 4, 'a', 5, 6, 'a', 7, 8, 'a', 9, 0]

Insert b in the said list after 4 th element:
[1, 2, 3, 4, 'b', 5, 6, 7, 8, 'b', 9, 0]

Pictorial Presentation:

Python List: Insert an element in a given list after every nth position.

Flowchart:

Flowchart: Insert an element in a given list after every nth position.

Visualize Python code execution:

The following tool visualize what the computer is doing step-by-step as it executes the said program:


Python Code Editor:

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Previous: Write a Python program to convert a given list of strings and characters to a single list of characters.
Next: Write a Python program to concatenate element-wise three given lists.

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Python: Tips of the Day

Big Number Readability:

you can separate zeros with underscore (_)

print(2_000_000)
print(2_000_000 +1)

Output:

2000000
2000001