How to Display Duplicate Number in a List in Python

[KingM]

In this tutorial, we will program 'How to Display Duplicate Numbers in a List in Python'. We will learn how to display all the possible duplicate numbers in a list. The objective is to automatically display the duplicates within a list. I will provide a sample program to demonstrate the actual coding process in this tutorial.

This topic is very easy to understand. Just follow the instructions I provide, and you can do it yourself with ease. The program I will show you covers the basics of programming to display duplicate numbers in a list. I will do my best to provide you with a simple method for displaying possible duplicates in a list. So, let's start with the coding.

Getting Started:

First you will have to download & install the Python IDLE's, here's the link for the Integrated Development And Learning Environment for Python https://www.python.org/downloads/.

Creating Main Function

This is the main function of the application. The following code will display a simple GUI in terminal console that will display program. To do this, simply copy and paste these blocks of code into the IDLE text editor.

1. ret =
   
   False
   
2. 
   
3. 
   
4. while
   
   True
   
   :
   
5. print
   
   (
   
   "\n
   
   ================== Display Duplicate Number in a List ==================\n
   
   \n
   
   "
   
   )
   
6. 
   
7. 
   
8. 
   
9. list
   
   =
   
   [
   
   22
   
   ,
   
   22
   
   ,
   
   4
   
   ,
   
   5
   
   ,
   
   6
   
   ,
   
   4
   
   ,
   
   5
   
   ,
   
   7
   
   ,
   
   12
   
   ,
   
   12
   
   ,
   
   15
   
   ,
   
   14
   
   ,
   
   16
   
   ,
   
   16
   
   ]
   
10. 
    
11. print
    
    (
    
    "My List: "
    
    ,
    
    list
    
    )
    
12. 
    
13. dup =
    
    [
    
    ]
    
14. 
    
15. for
    
    a in
    
    list
    
    :
    
16. 
    
17. 
    
18. n =
    
    list
    
    .count
    
    (
    
    a)
    
19. 
    
20. 
    
21. if
    
    n >
    
    1
    
    :
    
22. 
    
23. if
    
    dup.count
    
    (
    
    a)
    
    ==
    
    0
    
    :
    
24. 
    
25. dup.append
    
    (
    
    a)
    
26. 
    
27. print
    
    (
    
    "Duplicate number: "
    
    ,
    
    dup)
    
28. 
    
29. opt =
    
    input
    
    (
    
    "\n
    
    Do you want to try again?(yes/no): "
    
    )
    
30. 
    
31. if
    
    opt.lower
    
    (
    
    )
    
    ==
    
    'yes'
    
    :
    
32. ret=
    
    False
    
33. elif
    
    opt.lower
    
    (
    
    )
    
    ==
    
    'no'
    
    :
    
34. ret=
    
    True
    
35. print
    
    (
    
    "Exiting program...."
    
    )
    
36. 
    
37. else
    
    :
    
38. print
    
    (
    
    "Please enter yes/no:"
    
    )
    
39. break
    
40. 
    
41. if
    
    ret ==
    
    False
    
    :
    
42. continue
    

This script finds and displays duplicate numbers in a predefined list. It repeatedly prompts the user to rerun the process or exit the program. Each time, it prints the list and its duplicate numbers, allowing the user to choose whether to continue or exit based on their input.

Output:

The How to Display Duplicate Number in a List in Python source code that I provide can be download below. Please kindly click the download button.

There you have it we successfully created How to Display Duplicate Number in a List in Python. I hope that this simple tutorial help you to what you are looking for. For more updates and tutorials just kindly visit this site. Enjoy Coding!

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