Python Program to Remove Duplicates from a List

Introduction

Removing duplicates from a list is a common task in data processing and analysis. Duplicates can occur when data is collected from various sources or when data entries are repeated. This tutorial will guide you through creating a Python program that removes duplicates from a given list, leaving only unique elements.

Example:

Input: [1, 2, 2, 3, 4, 4, 5]
Output: [1, 2, 3, 4, 5]
Input: [10, 20, 20, 30, 40, 40, 50]
Output: [10, 20, 30, 40, 50]

Problem Statement

Create a Python program that:

Takes a list of numbers as input.
Removes any duplicate elements in the list.
Displays the list with duplicates removed.

Solution Steps

Take Input from the User: Use the input() function to get a list of numbers from the user.
Convert Input to a List of Integers: Convert the input string to a list of integers.
Remove Duplicates: Convert the list to a set to automatically remove duplicates, then convert it back to a list.
Display the List Without Duplicates: Use the print() function to display the list with duplicates removed.

Python Program

# Python Program to Remove Duplicates from a List
# Author: https://www.rameshfadatare.com/

# Step 1: Take input from the user
input_list = input("Enter a list of numbers separated by spaces: ")

# Step 2: Convert the input string to a list of integers
numbers = list(map(int, input_list.split()))

# Step 3: Remove duplicates by converting the list to a set, then back to a list
unique_numbers = list(set(numbers))

# Step 4: Display the list without duplicates
print(f"The list without duplicates is: {unique_numbers}")

Explanation

Step 1: Take Input from the User

The input() function prompts the user to enter a list of numbers, separated by spaces. The input is stored as a string in the variable input_list.

Step 2: Convert Input to a List of Integers

The split() method is used to split the input string into individual components, and map(int, ...) is used to convert these components into integers. The list() function then creates a list of these integers.

Step 3: Remove Duplicates

The list is converted to a set using the set() function, which automatically removes any duplicate elements. The set is then converted back to a list to maintain the list format.

Step 4: Display the List Without Duplicates

The print() function is used to display the list with duplicates removed.

Output Example

Example 1:

Enter a list of numbers separated by spaces: 1 2 2 3 4 4 5
The list without duplicates is: [1, 2, 3, 4, 5]

Example 2:

Enter a list of numbers separated by spaces: 10 20 20 30 40 40 50
The list without duplicates is: [10, 20, 30, 40, 50]

Example 3:

Enter a list of numbers separated by spaces: 5 10 5 15 20 20
The list without duplicates is: [20, 10, 5, 15]

(Note: The order of elements in the output may vary because sets do not maintain order.)

Conclusion

This Python program demonstrates how to remove duplicates from a list using a set, which is an efficient and straightforward method. Understanding how to handle duplicates is important in data processing and helps ensure that your data is clean and accurate.