Element with Largest Frequency in List

We are given a list we need to find the element with largest frequency in a list . For example, we are having a list a = [1, 2, 2, 3, 3, 3, 4, 4, 4, 4] we need to find the element with most frequency which will be 4 in this case.

Using collections.Counter

Counter is a convenient way to count elements and get the most common one directly.

from collections import Counter

a = [1, 2, 2, 3, 3, 3, 4, 4, 4, 4]
c = Counter(a)
f = c.most_common(1)[0][0]  # Get the element with highest frequency

print(f)  

4

Explanation:

• Counter(a) creates a dictionary-like object that counts the frequency of each element in the list a.
• most_common(1) method returns most frequent element as a list of tuples and [0][0] extracts the element itself. In this case output is 4 element with highest frequency.

Using max() with count()

We can use max() with count() to find the element with highest frequency by checking the count of each element.

a = [1, 2, 2, 3, 3, 3, 4, 4, 4, 4]
m = max(set(a), key=a.count)  # Find element with maximum count

print(m)  

4

Explanation:

• set(a) converts the list a into a set removing duplicates so only unique elements remain.
• max(..., key=a.count) function finds element in the set with the highest count in the original list a and in this case it returns element with the most occurrences.

Using a Dictionary to Count Occurrences

We can manually count occurrences of each element and then find the one with largest count.

a = [1, 2, 2, 3, 3, 3, 4, 4, 4, 4]
f = {}

for num in a:
    f[num] = f.get(num, 0) + 1

m = max(f, key=f.get)  # Get the key with max value

print(m)  

4

Explanation:

• for loop iterates through list a and f.get(num, 0) + 1 expression counts occurrences of each number storing them in dictionary f.
• max(f, key=f.get) finds key in dictionary f with highest value and it returns 4 element with highest count.

Using sorted()

We can sort list based on frequency and then pick the element with highest frequency.

a = [1, 2, 2, 3, 3, 3, 4, 4, 4, 4]
# Sort unique elements based on their frequency in descending order  
m = sorted(set(a), key=lambda x: a.count(x), reverse=True)[0]

print(m)  

4

Explanation:

• set(a) extracts unique elements from a and sorted(..., key=lambda x: a.count(x), reverse=True) sorts them in descending order based on their frequency in a.
• [0] retrieves the first element from the sorted list which is the one with the highest frequency in this case 4