# 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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**Previous:** Find the product of the units digits in the numbers.

**Next:** Find the numbers that are greater than 10 and have odd first and last digits.

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## Python: Tips of the Day

**Decapitalizes the first letter of a string:**

Example:

def tips_decapitalize(s, upper_rest=False): return s[:1].lower() + (s[1:].upper() if upper_rest else s[1:]) print(tips_decapitalize('PythonTips')) print(tips_decapitalize('PythonTips', True))

Output:

pythonTips pYTHONTIPS

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