Here's Python Program for List Duplicates

Here is a program to find the item that occurs most frequently in a data structure. So why to find frequent item? Maybe it is the most purchased item on your shopping site. Perhaps it is the web page that gets hit the most often.

If you are a tester, it could easily be the test that has had the most failures over the last year. Whatever it is, you want an easy way to find the data you need, and Python is here to help you.

Python List duplicates

Here are the two simple lists:

list_1 = [1,2,3,2,3,2] 

list_2 = ['a', 'b', 'a', 'b', 'c']

• We can't do simple math on the individual items since the second list contains characters. For example, it could contain the words of a book, and you want to find the most commonly used word in the work. 

• Also, it maybe list of UPC values for commonly purchased items. Whatever it is, all we can guarantee is that the data is probably comparable, in that we can compare one of the items to another. Yet we need to find frequent items.

• Here is a simple brute force approach to get a resolution for this problem.

Python program

Below, you will find a program to find repeated values.

list_1 = [1,2,3,2,3,2]

list_2 = ['a', 'b', 'a', 'b', 'c']

def most_common_brute_force(l):

  # Find the counts of all elements

    dict_of_counts = {}

    for i in l:

        if i in dict_of_counts.keys():

            dict_of_counts[i] = dict_of_counts[i] + 1

        else:

            dict_of_counts[i] = 1

            max_count = -1

            max_value = -1

 

        for k, v in dict_of_counts.items():

            if v > max_count:

                max_count = v

                max_value = k

    return max_value

print(most_common_brute_force(list_1))

print(most_common_brute_force(list_2))

Output

2

a