Python: Remove duplicates from a list of integers, preserving order

Python Programming Puzzles: Exercise-54 with Solution

Write a Python program to remove duplicates from a list of integers, preserving order.

Input:
[1, 3, 4, 10, 4, 1, 43]
Output:
[1, 3, 4, 10, 43]

Input:
[10, 11, 13, 23, 11, 25, 23, 76, 99]
Output:
[10, 11, 13, 23, 25, 76, 99]

Pictorial Presentation:

Sample Solution-1:

Python Code:

#License: https://bit.ly/3oLErEI

def test(nums):
    return list(dict.fromkeys(nums)) 
nums = [1, 3, 4, 10, 4, 1, 43]
print("Original list of numbers:")
print(nums)
print("Remove duplicates from the said list of integers, preserving order:")
print(test(nums))
nums = [10, 11, 13, 23, 11, 25, 23, 76, 99]
print("\nOriginal list of numbers:")
print(nums)
print("Remove duplicates from the said list of integers, preserving order:")
print(test(nums)) 

Sample Output:

Original list of numbers:
[1, 3, 4, 10, 4, 1, 43]
Remove duplicates from the said list of integers, preserving order:
[1, 3, 4, 10, 43]

Original list of numbers:
[10, 11, 13, 23, 11, 25, 23, 76, 99]
Remove duplicates from the said list of integers, preserving order:
[10, 11, 13, 23, 25, 76, 99]

Flowchart:

Visualize Python code execution:

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

Sample Solution-2:

Python Code:

#License: https://bit.ly/3oLErEI

def test(nums):
    result = []
    for x in nums:
        if x not in result:
            result.append(x)
    return result
              
 
nums = [1, 3, 4, 10, 4, 1, 43]
print("Original list of numbers:")
print(nums)
print("Remove duplicates from the said list of integers, preserving order:")
print(test(nums))
nums = [10, 11, 13, 23, 11, 25, 23, 76, 99]
print("\nOriginal list of numbers:")
print(nums)
print("Remove duplicates from the said list of integers, preserving order:")
print(test(nums))

Sample Output:

Original list of numbers:
[1, 3, 4, 10, 4, 1, 43]
Remove duplicates from the said list of integers, preserving order:
[1, 3, 4, 10, 43]

Original list of numbers:
[10, 11, 13, 23, 11, 25, 23, 76, 99]
Remove duplicates from the said list of integers, preserving order:
[10, 11, 13, 23, 25, 76, 99]

Flowchart:

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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